Some random thoughts from me:
1.) You’re pretty patient, I think after four years of giving somebody a place to live rent-free, I’d be snarly. (I had a friend move in with me for what was supposed to be six months while she tried to put her life back together. It took a year and a half, and I was fairly irate by the time she left.)
2.) The agreement was for her and her kids, not her, her kids, and random guys. I had to have a chat with said above roommate of mine once about her boyfriend–I didn’t care about him spending the night once or twice a week, but more than that, and I was going to consider him a third roommate who needed to pay his share. Basically, I was making sure she understood I while I didn’t mind helping
her out, I owed her had-a-job-and-a-place-to-live-boyfriend squat.
3.) While you are not required to support their wedding by being a witness, it is also not your place to call it illicit just because she’s decided the rules of your church no longer suit her. If the law recognizes her marriage, she’s married, and it’s not illicit.
Code:
a.) If they're offering to pay rent, I don't see the issue in letting them stay. (And if she has a source of financial support in the form of a husband, then she jolly well should offer to pay rent.)
b.) If they're not offering to pay rent, husband or not, boot 'em all out.
My two cents.