DEAR SOMEONE ELSE’S MOM: My older sister has dated a few really nice guys, but even if they’re cruds, she gives up all her interests and a lot of her own social life for whoever she’s with.

Sometimes that can be hurtful to the rest of the people in her life. I know my dad was hurt by her not helping him out during his post-surgical rehab because she was so busy helping her then-boyfriend launch his new business.

She did the same kind of thing to our mother, who had a really hard time when our grandmother passed, and our mother kept reaching out to my sister to just come and keep her company. At that time, my sister was living with a guy who was big into sports, and they spent most weekends chasing his favorite teams during a really dark winter for our mom.

She’s stood me and her friends up, dropped her own interests to become obsessed with whatever the guy of the hour is into, and just in general becomes invisible with each relationship.

I love my sister, and hate seeing how she is when things end with a guy, but I also want her to understand there are more people in the world counting on her and caring about her than just the guy she’s with at the time.

How do I do that? --- SISTER OF THE INVISIBLE GIRLFRIEND

DEAR SISTER OF THE INVISIBLE GIRLFRIEND: While I see it as healthy in a relationship for both parties to take some interest in each other’s pursuits, I agree with you that when one of the parties completely loses themselves, it’s ultimately not good for the relationship, the people in it, or those close to the couple.

It might help if the people who count on her and keep getting let down go beyond asking for her help. She needs to directly and clearly hear how much her not being there for them hurts. If it comes from both family members and her closest friends, and if she hears it enough, maybe she’ll start stepping in and showing up when she’s needed.

Otherwise, in her love-blinded state, she’ll most likely continue to take it for granted that all’s well with the world outside her happy little bubble.

DEAR SOMEONE ELSE’S MOM: My son met a woman who started working as a cashier at the pharmacy where he’s an assistant manager. She is the divorced mother of two tweens, and my son just turned 23. He has been in two longer-term relationships, and both of his former girlfriends ended things after over a year together. I think if that hadn’t been the case, he would have been married by now.

I have met his new girlfriend and she seems like a nice person. I also feel my son is a good judge of character. But I worry about him stepping into a ready-made family, with kids not that much younger than he is. There is also the ex-husband, who from what he’s heard, is still very involved in his kids’ lives.

I think it’s a lot for my son to take on, and often wonder if I should say something to him about my feelings. It would not be about his girlfriend, but just her situation in life versus his. Or, do I continue keeping my worries to myself? --- MOM ON THE FENCE

DEAR MOM ON THE FENCE: You state that your son’s a good judge of character. That and the fact that at a fairly young age he’s been put in a management role, albeit a junior one, suggest to me he may be more mature than many of his peers.

Even if you had less reason to have faith in your son’s judgement, I’m not sure anything would be gained by sharing your concerns with him about his new relationship. Time will tell if this one’s a keeper, and it’s ultimately up to him and his new girlfriend to decide if they can make it work, especially with her children as part of the picture.

DEAR SOMEONE ELSE’S MOM: My mom and dad split when I was really young, and my dad moved away and started a new family. My mom raised my brother and me mostly on her own, although my dad always supported us financially, including paying for college.

He wanted us both to become lawyers, like him, which suited my brother, but not me. I am working on my master’s in social work, and while I am paying for that myself, my dad always makes sure he lets me know what a mistake he thinks I’m making. He tells me I could do more good in the world by being a state’s attorney, or even working as a public defender, if I want to be of use to others. He thinks I am throwing away a good mind on a mediocre career.

I am perfectly happy with the path I’m taking. I can think of no better way to serve my community than the one I’ve chosen, regardless of what my father thinks.

Why can’t he lay off his criticism and just support my goals? --- NOT MY FATHER

DEAR NOT MY FATHER: It’s hard to be a parent and not have a vision for how you think your child’s life should or could go.

You’re following your own dreams, in your own way, and as I see it, the best you can do for now is to continue reminding your father of that. He’s perhaps been very happy with his career choices, and now you need to affirm that you’ve found what you believe will make you equally happy, and that you have the same right as he did to make your own way in the field of your choosing.