Yes you need to get on FetLife for this discussion. You'll find what you're looking for there.

You'll need to educate yourself on what an open marriage is bec it's not just sleeping around. Most are in a poly relationships which has rules, dimensions & boundaries, but there are marriages of swingers which is totally different.
FetLife has a great deal to read on these subjects. I'm always being updated on what I thought I knew...& what I now understand.
It makes a big difference.
And if you're not educated many will not vet you into the Community.

You'll also find a lot of people into your fetishes, your local munch group that may have connections for you being around like minded people.
Good luck!