1.) can you look for a less noisy, ant-free apartment?
2.) if you do decide to move in with your boyfriend, don't sink all your former rent money into improving the place right away. It would be tempting, but don't do it. Instead, squirrel away aside enough money each month (in your own account!) so that if the situation blows up, you can get away fast. I used to live in a homeless shelter, and can't begin to count the number of women living there who ended up homeless because they didn't look into protecting their interests ahead of time. And if you do move in, make it a "test run" for say, 6 months, with certain goals in mind...like, that other house to have certain repairs on a certain schedule. That way you'll have some idea what a future there is to look like. You don't want to get suckered into an unhealthy situation, or an unsafe one. Get things on paper, no matter what your boyfriend says. Pay some kind of rent...and not with cash. This isn't an either/or: you still have options. If you can't see clearly enough to do this, I think you'd be better off in your own apartment. Just my take on things. Good luck.