Sometimes we know the answers we're seeking, but it helps to just see/hear it from ourselves or others. It certainly helps me to externalize things. Makes them feel less trapped inside me.
I was friends with a guy for a couple years. He and I were pretty flirty with each other. Finally, one day I went for a walk with him and told him that I was attracted to him, but didn't do monogamy very well and didn't want to be "serious" with him. I said that my boyfriend was fine with whatever I did with other men. He never gave me a response and I didn't hear from him again, so that was that. I felt sad that it severed our friendship, but at least I took the risk. I think I scared him.
Anyway, you never know until you do it.