Owner occupied roommate issue

[Andrew Vaught]

Hey all,

3 months ago I got a roommate for my townhouse. She's in her 40s and going through a divorce; she just needed her own space while it's in progress. Initially she asked if she could bring over one of her 3 kids once a week. I said of course. Shortly after that she asked if her two boys (10yr and 12yr) could stay here every other week for an extra $100/mo on her rent. Being a child of divorce, I'm sympathetic to the situation. Around early May she asked if one of her old flames could stay with us for a month or more, I told her no because I'm not comfortable since I don't know him and I don't want another roommate. Apparently he got his own room for rent in the city but he's at my house 5-6 days a week. It's getting more and more on my nerves since 1) I told her I don't want him living here 2) he doesn't pay rent and 3) I don't want another roommate.

I don't want to burn the bridge with my roommate because she's interested in renting my whole house when I move out, which is perfect. And she is a great roommate, aside from this particular issue. Does anyone have advice on how to handle this type of situation with grace and diplomacy?