Lissie was right on as usual with her advice. Only you know your heart, so giving someone a road map just doesn't work. What would be the best thing for you? You have so much going on right now with your health and I think that you need to consider that. If being his friend is going to give you the peace that's necessary then go for it. It's your call. Separation is hard enough, but your health has got to take priority!
Just wanted you to know that you are in my thoughts and prayers and that I have asked for you to be put on a prayer chain at church.