Well, it could be something totally innocent and the anger is coming from his resentment that is built up, over the years. Repeated sexual rejection is really a damaging thing. Imagine how you would feel, being rejected. Specifically, what feelings would flood over you? Could you remain loving to your spouse after years of this? I'm not saying this to induce guilt, btw, but to illustrate what a powerful tool empathy can be. Put yourself in the other person's shoes, as fully and completely as you can, and it can really be eye opening. When I do this (remember to do it, really) and think of how our R looks from his LD standpoint, I am much more loving and caring towards him.
So, the HD partner begins to hate themselves because they feel worthless and undesirable. And they begin to hate the other person because they are "making" you feel that way. Illogical, yes. He is who he is, regardless of what YOU think about him. If he's a sexy guy, he's a sexy guy no matter how many times you reject him. But......it takes a while to come to that realization on your own, kwim? Give him some time and lots of love and see what happens to that anger.
The other not-so-innocent explanation is that your love and recommitment to the sexual relationship is causing him guilt and uncertainty with respect to the OW.
I don't know what to tell you about that one, except to simultaneously keep a close eye on what's going on, but be the best Bananas you can be. Lure him to you with your great personality and sexy fun attitude. This is what got him the first time, right!
I think you are right, in that we all sorta get lax and lazy about being the fun person that drew us to each other in the first place. Try to get her back and chalk the rest up to lessons learned.
