Continued...
Husband's idea was that I would only do the occasional thing at the gym, but I pointed out that that was both risky in terms getting caught as well as risky regardings infections, etc. He was distraught but I reassured him that if I didn't really love him unconditionally I would have left years ago. His 2 best friends apparently said something similar, because things have settled and I'm still having fun.
This last bit interests me, as my partner and I have terms to our limited openness. Over the last couple of years, we have both discussed what is on the table, and what is forbidden. Occasional gym play, maybe a random hook-up when traveling, giving someone a handjob at a urinal..light things, but fun things. Meeting someone, and having a relationship? Definitely not.
Fun, casual play: absolutely. An affair: no.
Because that is what it boils down to if you develop a relationship, at least in our eyes. Granted, some people have polyamorous relationships and that works well for them. For us, our relationship is the only one we want to nurture.
Although, now that I am discussing this, I am reminded of people in both our lives where more-than-platonic feelings exist, and to whom certain freedoms are granted. So, to expand a bit on that.. Those 2 other people, one that I like and one that he likes, are both married to women and have kids. They will not leave their current relationship, and neither will we. Yet, over the years, more has developed with me and my friend, and with my partner and his friend. It's there. We recognize it and have talked about it openly to each other. There hasn't been any sex in those years, yet, but it could happen, and if it did it would be ok.
So, I guess my addition to this conversation is that there aren't absolutes of laws, and that even with agreements there are exceptions. It all depends on your partner, and you.
The biggest thing is communication. Clear and open communication. Hiding and secrets fester, and create a whole other set of behavior that goes against what opening your relationship was supposed to be about from the outset.