Well it sounds like you need to make a decision.

Is this situation okay with you? If not, then you need to say goodbye to him.

Don't just 'not talk to him again'. That's just plain rude. Especially since you've spent five months together. If you're going to break it off, then you need to tell him. Disappearing into the sunset is a flaky thing to do.

If it all comes down to what is this woman's role in his life, then point blank ask him those three things above. If he doesn't give you answers you're satisfied with, then you have your answer as to what you need to do.