Relationships and Hobbying or Providing

How does it work? Do you have your SO on board? Do you hide it?

I am currently in an ending marriage due to cheating. I was absolutely faithful to her for years, then she cheated on me. I'm still married, but all that monogamy crap is out the window.

How does it work for you folks?
I have never ever once cheated on a partner or given her a reason to feel jealous/insecure but then again I have never kept a partner for that long. Trade them in like cars. I find that easier than lying and cheating although not necessarily better.