One thing you should always keep in mind is that his wife and family will always come before you, no matter how many problems he claims to have at home. Keeping you as his secret mistress is an obvious sign that he is not ready to lose his spouse. If he was, then he would just leave her and be with you, but instead- he has chosen to spare her the pain and embarrassment because he loves her- and will continue to keep you a secret for as long as you let him. Are you ready to be second priority?
I should know, been there, done that...so beware of the consequences.
Proverbs chapter 22
14 Adultery is a trap-it catches those with whom the Lord is angry.