Hiya.
Yeah, she was a cop too, but remember she said she wanted to give it all up someday to have a family. She said that in "The Big Fall" and whatever ep. with the lawyer...Jason..?? (I think) Rick said something about her (and Jason) having little McCall's hopping around someday. I guess like in the new movie she was going to work in juvenile division or something.
I can't get past the idea of Alex just showing up like that either. A flashback or something to give us an idea of the "past" romance/relationship would have worked. Well, not that I'd be super happy about her running off with Alex, but at least we'd know something about him.