So you want to go from an emotionally abusive relationship to a controlling relationship with a married man who tells you that things will be different once you are alone. How will it be different? Oh yeah, he will be able to screw you whenever he wants since you will be alone and he will not have to leave his family in order to get some pussy on the side. Sounds like a really sweet deal for him. For you, not so much.
If your marriage is intolerable, then end it. Take some time to get your life together. Find a single guy who will treat you like you deserve to be treated. And most importantly, walk away from the married guy. You are being used for his enjoyment. Why would you want to whore yourself out to someone like that. (I used the word whore intentionally. It is exactly what you would call a woman your husband was seeing on the side. And I would bet it is exactly what your lover's wife would call you if she finds out about you.)