my mess

So me and this guy have been best friends for a while. I'd never get feelings that I really like him in any other way than a friend. Right now I have had a boyfriend for 5 months and we hit a little rocky patch. My best friend is my go to when I'm sad, mad, angry or happy. So he knows a lot. So I tell him everything and he tells me everything. He's sometimes a little flirty but I brush it off. This month I started feeling real feelings for him other than friend feelings. We talked about it and he told me he's had a crush but tried to ignore it when I got a boyfriend. That he's always loved me. Now here is where it gets complicated.

Both of us have significant others. Yet we both don't want to ruin our friendship just because of this. But in my eyes he's the total package but my boyfriend is the sweetest guy I know.

WHAT DO I DO.