When I moved two years ago I moved an apartment over from an attractive single girl. We slowly got to know each other and developed a small friendship. In the course of that time she began dating another man whom I also got to know and likewise became friends with. He moved into her apartment and we have all since become very close friends spending significant time together several times a week. My friendship with both of them feels very independent of their relationship and the three of us are quite comfortable together no matter if any two of us are together or all three of us.
In short, we are all mutually close and fond of one another, I value both friendships, their own relationship, and am confident they feel the same about me.
I have developed feelings for this woman. I do not entertain the idea of being with her, even though I suspect she may have mildly romantic feelings for me despite her relationship. I do not want to end our friendship but I fear my own feelings in this matter and I think it is too late to hope that they can be denied without causing me pain.
I don't know what to do. Lately, I have tried to subtly distance myself from them, but it is not easy to do as they BOTH encourage me to be present. I am afraid that I think the right course of action may be to confess my feelings at least to the point that they understand it may be best for all of us if their friendship with me comes to an end, at least temporarily.