Ex wants to move in.....

A little background, married for 15 years, wife left to move in with boyfriend in a different state about a year ago. We divorced as quickly after that as possible. 3 kids. I got full custody in the divorce in a state where that is very rare.

So my ex shows up at my doorstep because she's leaving her boyfriend. My kids let her inside because it's 'mom' and I haven't told them not to, I'm not sure if I should or not, my issues with their mother aren't theirs to deal with and I want them to have as best a relationship they can with her. Anyway she just wants me to hold her, so I hug her for a minute and then she lets me know she's leaving her boyfriend and she wants to move back in to the spare bedroom, if possible. I tell her no, it's not possible, why doesn't she move in with her parents till she's back on her feat. She says she doesn't want her mom telling her she told her so. I just rolled my eyes and let the conversation die.

I wanted to fix it for her still. It took a lot to just sit there and say nothing till she got uncomfortable enough to leave. Maybe I should have just told her to get out. I don't know, I know she can't be in my life again.

Edit: Thanks everyone for your kind comments and commiserations. I'm glad I have you guys and gals around.