Thanks I'm glad you didnt think me rude. Sometimes I just call a spade a spade.
Ok this guy is a Virgo but at the end of the day he is a guy. I know a few Virgo guys (have known a lot more Virgo women) but moreover I know a few Cancerian women and get along very well with them (I also have the watery crabe prominent in my chart so I have a natural affinity). Scorpio and Pisces remain an enigma to me! So what I will say is I know how Cancer can get sentimental and are kind hearted individuals - you want to think the best of people (ie if I just help enough maybe he will suddenly get the strength to do the right thing, oh been there and boy, that really is a waste of energy!) He is just taking advantage. You know, sadly, that you cannot be a friend with this guy. I myself have tried to be 'friends' or stay 'friends' with married men who have come on to me (I felt sorry for them too, sap that I have been, only to get angry with them because it is always about them). To you it might be friendship but to them it is a foot in the door because men can't be friends with women, fundamentally, the way women are friends with other women.
In the book 'he's not the into you' they say: he's not that into you if he wants to have an affair with you. It does show a lack of respect for you (and of course his wife). I'm not meaning to be blunt here, once again
I feel, as you say, that this is a life lesson for you (as for him). You recognise it as a pattern so this tells you a lot. Also I think sometimes you have to let go and 'let God' (if you will) to see if he truly is the right one for you. I personally don't believe affairs are ever a good thing, but I also know that life is not black and white and that serendipity can sometimes prevail and you can hit relationship gold, so I am not meaning to judge your journey.
But you know the truth in your heart - prayer can be helpful too (if you're into that!)
From my experience guys seem to learn lessons a lot slower than women. Life literally has to hit them on the head with a large blunt object, burn their house down and run over their dog before they think: "Gee, mmm maybe there's something I need to take a look at?" I'm not dissing guys really, because they make interesting case studies, afterall (tee hee;-) But you get my point, I'm sure.
Anyhow I wish you the best - you deserve someone awesome.