Hi MiamiTemp, welcome to the forum
Hmmm there are not words of wisdom in something like this... To be a friend of benefit while wanting to be more is a startingpoint that will leave you under every circumstance hurt in the end if he didn't and doesn't want more.
I understand you feel pain looking reality in the eye, but just think about that other woman who has no idea she is being cheated on.....
Personally I wouldn't want to have anything to do with cheating liers.
I am sorry to be harsh, but this is the 'sound of honesty' speaking.
I would cut ties with him if i were you. No matter how difficult and no matter how shattered I would feel.