Just an update for you all:
The guy has come around to our house to fuck my wife several times now. I just love sitting outside the bedroom and listening to my wife moan, unfortunately they both don't want me actually present. The highlight for me so far was when he spent the whole night at our house for the first time. We all watched a movie together with them two cuddling up together on the sofa. He asked me several times if i was sure i was okay, my wife just said he is fine. She had his hands down his pants and they were both touching each other up and kissing. After the film ended my wife said to me "show him your little dick", he said no but she said again show him. I pulled my pants down and they both laughed then my wife then said "you know i still love you" and then both of them went upstairs.
I spent the next few hours listening to them fuck from the spare room, it was amazing.
Strangely in the morning before he left he apologised for laughing at me, I said it was okay. I would prefer it if he was much more mean and horrible to me but he is really polite and nice to me, when he is not fucking my wife that is.