My cousin is looking for a job and staying with us.

in any case, you are not fit to talk to him.

only let your boyfriend talk to him. Even if you are right, he will be disgusted.

as for what to say about him, just ask him what his plan is. If you don't have any good plans, you might as well go back. The expenses there are too high. It would be better if you have any plans. If there is a future, it won't be like this again.

You can ask your boyfriend to talk to him about the time you found out and put some pressure on him. Let him know that it is no good fooling around with you.