Update: he has messaged me. He was deeply hurt with what I accused him of and how I questioned his integrity, honor, and character (this is something he prides himself on and it is also something I've never questioned him on). He's making it a point to talk with the female coworker to make sure their friendship is as pure as possible so there is no questions coming from me or anyone else. But he is extremely hurt, offended, and appalled at what I did.
I did not mean to do any of those things, it's something I wasn't even thinking about.
So how do I go about apologizing and moving forward?