Who here tolerates "nasty" individuals for the sake of hanging on to loved ones?

Here's my "Dear Abby" letter for the Lounge:

My sister, god love her heart, has a track record of being attracted to men who take advantage of her. Now in her mid-40s, she's on her third long-term relationship with a guy who is fully capable of working but chooses to work very little or not at all, so he sponges off of her.

Making matters worse, he's lied to her, repeatedly. And he cheated on her twice (maybe more, but we know of two occasions with different women, for sure). After finding out about his philandering each time, we had very blunt conversations with her, telling her that she's much better off without him. They broke up briefly, yet she's gone back to him each time. So frustrating!

My assessment: she has low self-esteem and she finds men who she "can take care of" so they'll see value in her and then she hopes they'll eventually love her for who she is.

Not bad enough? He's a Trump-humper and his views have been rubbing off on her. She and I periodically have political arguments these days, which was never true in the past.

My wife and I don't associate with him and we made that clear to my sister quite a while ago. However, after several months of her and her deadbeat boyfriend living together without any incidents (just a matter of time, IMO), she's trying to get all of us together for dinner in hopes of normalizing relations.

My inclination is to reassert my position that she is always welcome to stop by but he remains persona non grata. I figure I'm running the risk of an ultimatum pretty soon: "If you don't accept him, you don't accept me."

Just wondering how many of you are in a similar boat and whether you put up with a loser who's part of a relative's life so that you don't lose that loved one long-term (maybe forever), or do you hold firm and refuse to interact with the jackass?