However....

This is a common situation and there are loads and loads of opinions strewn throughout the forum... from on how to broach the subject with a vanilla partner, to the futility of trying to change a vanilla partner. From what's cheating to what's polyamory. From online to real life.

So I suggest you do a lot of reading and then ask questions of the individuals whose opinions you find most aligned with your needs. There is no one answer...