It sounds like he can only relate to you or perceive you in one way, which is at it interests him or relates to him.
If you're not playing his game and responding the way he wants -- whatever that might be...from what you've said, I'm presuming he wants lots of booklicking and flirting, etc. -- now he's finally got the message that you're not interested in casual sex, he's surly and/or uninterested.
I would continue to be courteous and leave it at that. However, if you are unable to work around him, I would look elsewhere for work if at all possible.
I was in a hostile work environment years ago right out of school where I was being harassed by this one man who was about 40 and I was early to mid 20s, and their solution was to offer to send me to "assertiveness training" (eyeroll)...I said no, they tried to screw me on my review. I refused to sign it. I reported the whole thing to the HR attorney and also to the one senior female VP but I also left. Later I found everyone above this guy got demoted.
But as far as I know he was not let go at that time, which was some sort of CYA thing...that would be some sort of admission of liability. So just FYI...I am glad I left. Let them deal with that slimeball - I assume they'd resent the hell out of him for getting them demoted but who knows? Better to leave and find a place where you are treated with a bit more respect.
Treat it like a workplace issue and document it, including all historic events you can recall. All the rubbish he's put on you. Keep your personal email copied and up to date with the events, and if you feel it's impacting your work, immediately shop your resume/CV around.
If he gets really hostile, then once you are ready to leave, I would report him to your supervisor and to HR and see how they handle it -- almost guaranteed they handle it badly, but I would then turn in your two weeks' along with filing complaints at your local, regional, and national employment and labour rights agencies. Let them follow up after you're gone.
Ideally it doesn't come to this, but if it does, no worries - just move on, keep your head up, and turn the page
You're a strong woman, so vote with your feet and report them all to the agencies if they don't have your back in this situation.
Peace & blessings