DEAR KRISTIN: I live in a large home with several roommates. At first, we all got along beautifully, but after a few months the cracks in the armor began to appear. We’re all young professional women on our way up the career ladder, but it’s beginning to feel like an elementary school slumber party gone wrong. One roommate’s constantly swiping my food (“sneaking a few grapes right quick,” is how she describes it), and another has a bit of a drinking problem.

I can’t afford to live by myself and to be completely honest, I don’t WANT to live by myself ‘cause I’ll be lonely. I know this sounds like a sophomoric problem, but when you’re living it out in real time, it’s not so sophomoric at all. I’m kinda between a rock and a hard place. Any suggestions?

DEAR ROCK: You’ve got some boundaries to set, some decisions to make and some actions to take. First off, tell Miss Sticky Fingers to quit stealing your food. She might think of it as “sneaking a few grapes right quick,” but it’s your food and she’s stealing it. Unless you want to starve and unless you want her to continue walking all over you, you must handle your affairs and demand that she stops all this nonsense -- and do it quickly before it settles into any more of a dangerous pattern than it already is.

You describe your situation as a “slumber party gone wrong” -- but the difference between an elementary school slumber party and your living situation is that all of you are good and grown women, so act like it. Mom and Dad aren’t standing at the top of the stairs, listening in and waiting to swoop down and save you. This is your life.

Consider either calling a house meeting to address the issues as a group, or speak directly to each roommate one-on-one. Avoid sounding angry or accusatory, but be direct. Offer up a solution -- namely, everybody needs to start respecting each other’s property, boundaries and emotional space -- and if they don’t adhere, then get the hell out. Look for a new place.

Ultimately, what it boils down to is the fact that you cannot control their actions -- but you can control your own actions, so if your attempts to adjust the situation go ignored, exercise the control you have over yourself and get out of Dodge.

And keep in mind that it’s not just your physical space over which you have total control and dominion, but your mental and emotional headspace, too! Mindset matters. Quit tricking yourself into believing that you’re in an inescapable quandary. Quandary? Yes. Inescapable? No.

For all my readers who might be experiencing similar frustrations in your own lives, I say this: Know yourself well enough to know when you’ve reached your saturation point. And once you‘ve reached it, change the situation.

No one else can define this saturation level for you BUT you -- and no one else can address this situation in a way that works best for you BUT you. Change is hard, but being unhappy and feeling trapped is even harder.

DEAR KRISTIN: I work in a small company, and I’m the oldest employee by far. My colleagues are certainly pleasant and professional enough, but I’m beginning to feel like they don’t see me or listen to me with as much care and intention as they do their younger contemporaries.

This is happening at home, too: As I age, my children and grandchildren are beginning to treat me -- what’s the word? -- more “gingerly,” almost like a fragile porcelain figurine or a piece of crystal that could break (or at least crack) at the slightest impact.

The worst part? It’s getting worse! The older I get, the more gingerly I’m being treated -- either that, or ignored completely. At work and at home, when I say something relevant or interesting, everybody looks so SURPRISED, as if they’re thinking, “Wow! Did that great idea or astute observation just come out of HER mouth?”

I’m feeling increasingly demoralized, insulted and resentful. I might be getting on in years, but dammit, don’t throw me out to pasture just yet. I have wisdom to share. Ideas to express. Warnings to issue. Grandchildren to enlighten. Life to live. I know I can’t stop the aging process -- even if I could, I wouldn’t want to -- but this “Handle with Care” crap is getting on my last nerve. I refuse to go gently into that good night. Take my hand and lead me from this place of frustration and resentment. -- I AM NOT INVISIBLE!

DEAR “NOT INVISIBLE!”: First, keep that fire in your belly -- just redirect the flame so that it’s burning positive energy, not negative. Stoke those feelings of frustration in a way that works for you and keeps you focused on remaining seen and heard by others. Try to kick the anger and resentment to the curb, though -- none of us are getting any younger (including you), and we don’t have time to waste carrying around resentments.

You must refuse to become invisible. Do not become complacent or accepting of this treatment. Whether you’re in the office or with your family, speak up. Stand up. Use your words.

Communicate clearly -- and without always being asked or invited, but simply because you feel like you have something to say. And once you’ve said it, if you feel like you’re being ignored or disregarded, share it again, this time more forcefully. (How about something like, “Maybe you didn’t hear me the first time I said it, but ...”)

Remind your colleagues and family members, through your words and your actions, that you do exist. You do matter. You are relevant.

The moment you begin to hang back, to become quieter and more complacent, to lose that fire in your belly and that determination in your spirit, you’re blending into that opaque horizon of invisibility.

Also remember that the folks around you might not even realize what they’re doing. Society has for so long been conditioned to listen to the loudest, the leanest, the strongest and most vocal, that it’s almost instinctive behavior -- so it’s your responsibility to shift this mindset.

I fully realize that not every aged and/or aging person is capable of stepping up with such gusto and flinging the condescension we so often receive back into the faces of the flingers. This is why it’s important for those who can step up to step up ... for all of us.

Remind the people around you that the aged and aging have precious wisdom, experience and knowledge to share, and that this segment of the population brings value and vision to the rest of the world. This population also has tremendous buying power, so to hear us and see us also makes good business.

Getting older should not feel like a punishment, but like the privilege it is.

So stoke that fire, Beloved. Refuse to go gently into that good night. Keep giving ‘em hell. We’re behind you a thousand percent.

DEAR KRISTIN: My brother Paul passed away about a year ago. He was my best friend, my closest confidant, my hero. Whether it’s fair or unfair, I’ve held every guy I’ve ever dated to the same standards as I held my brother -- a pretty high bar.

I’ve been dating a guy I really like (who has been very supportive and comforting to me as I grieve Paul’s death, by the way), but these days, every time I look at him, I am reminded of Paul, which ends up making me either very, very sad, or very, very mad. He’s a wonderful guy, but his presence only seems to make me miss my brother more intensely. So now, I’m not only grieving, but I’m resentful, too -- a caustic combination. Any words of wisdom? GREIVING AND CONFUSED

DEAR CONFUSED: First, my deepest condolences. Losing a sibling is painful; it’s like losing a part of yourself. Give your grief the respect it deserves, Beloved. Stand in its midst and face it head-on ... but don’t let your grief get too greedy. Don’t let it distort your perspective or confuse your thinking.

Your boyfriend is not your brother, and your brother was not your boyfriend. Give each of these loved ones the respect they deserve as well -- which means loving them enough to let them exist independently of each other. Don’t meld them into one. Love your partner and love the memory of your brother with the intensity and fullness they each deserve.

Here’s the thing to remember about grief: Grief is love. Grief is born out of love; it exists because of love. So even as your heart is hurting, let this “grief is love” concept shower you with comfort. No, it is not a magical elixir that will make your sadness instantly disappear -- but it does create a connective thread between you and the person you have lost. You hurt so much because you loved so much. Let this love lead you through the darkness of grief.

You should also see a professional. A grief counselor can help you develop methods and strategies for coping with your loss. We sometimes tend to put our mental health on the back burner when we’re in the midst of grief, but this is a mistake. Since we’re on the topic of love, you must love yourself enough to get the help you need to sort through these difficult times.

And try to cut your boyfriend some slack. You say he’s trying to lift some of the burden of grief from your shoulders, but by constantly comparing him to your brother, you’re only adding to this burden he is trying to remove. Don’t do that. Don’t give your grief that much power.

So open your heart to the concept that grief and love help define each other; they are bound together. But just because they are bound together doesn’t mean they must become tangled into a painful knot. Through purposeful thinking and professional counseling, you can untangle this knot. This is where you hold the control.

And cut your boyfriend some slack.