“My boyfriend keeps saying he will leave his wife. It has been 3 years. What can I do to make him leave her quicker?”
Your boyfriend is a married man. There is a reason he has not yet left his wife… and it is probably because he has no intention to. There is no point in trying to hurry him as it is unlikely that he will leave her. Unless you are happy with the status quo (and you do not seem to be), perhaps you might want to look into other options.
If you do rush your boyfriend, he might do something he’s not ready for, and then blame you. If it’s been three years, then it could be that he’s happy as he is. Breaking a marriage is no easy task. Try making yourself a little less available and see whether he reacts. Be prepared for any reaction, however, even the negative.