My boyfriend made it clear when we began dating that he was into having a semi-monogamous relationship — meaning that emotionally he would only want to commit to one person but physically he would want to have affairs, but he and I would plan and make terms and conditions for these escapades. I hadn't been in very many relationships and not in any that were as sexually open as what he proposed, but I really enjoy his company and there was a hot spark between us. We started seeing each other often and eventually started sleeping together and we became very serious. We are now living together.
There is a bit of an age gap, I am 22, and he is 29. He also wants me to stay thin and die my hair — both of which I do for him without much trouble. He continues to gain weight, drink in excess, and doesn't help with the housework — but from my understanding from some of my friends this is not uncommon for men.
He is always very open and brutally honest about everything, sometimes to the point of being caustic and hurtful. I like that in him but it can hurt sometimes. He's been dropping hints lately that he would like to take me up on the agreement we made about him having an affair. Since we've been together for nearly two and a half years now and have an active sex life (3-4 times a week on average) and a happy home I don't know why he wants to have another woman. I feel a little worried about how often this may come up. We're currently planning on the first clandestine meeting with a woman for his birthday, but I am apprehensive.
What's a girl to do with herself on the night she knows her lover is with another?