Tl;dr older male coworker has/had feeling for me and I didn't reciprocate. Now I'm promoted and he's fostering an environment to make our mutuals pick sides and ignoring me out right when I'm trying to build team unity. Eventually he will have to report to me for work as he's not on my team but he's unwilling to even talk to me or look at me and actively avoids me everywhere at work. Not sure if I should go to HR?
Sorry, this probably falls in a gray area and would love some advice and just someone to read and understand my situation. I'm at a corporate office setting. I'm a woman in my 30s who manages a few teams that rotate. For context, I used to be close friends with this man who's +10 years my senior. He's generally a very chill guy and I always found his conversations humorous and he reminded me a lot of my former friend who passed and a mentor. Let's call him G. A lot our coworkers/friends know that we were cool before but our friendship basically collapsed over the span of 2 years. It started off strong and we both had the same job title. We'd banter a lot however there ended up being a moment where he confessed his feelings to me and I didn't reciprocate. Then he started getting more upset with how we would banter and said I was bullying him and saying hurtful things when it would be something beign (ex. telling him to "get good" at mini golf during a group outing with other friends).
The 2 big event which impacted our falling out was that another coworker and I were alumni from the same college. I'd make an effort to make him feel included in the office and we would all just joke around about silly things and leave dumb sticky note drawings on everyone's desks. One day the other coworker asked what's our deepest fears and G said the deep ocean and the other coworker said he'd also be afraid of Pacific rim monsters coming out and attacking him. I laughed because it was so left field of a response to a genuine fear. Apparently that angered G and he pulled him aside and said how the other coworker was bullying him and made me laugh at him. The other coworker texted me saying he's really sorry if he crossed a line because G listed all these grievances he had no idea about. I ended up going to G and asking what happened and he said all these things. I thought about it and I said that sucked he did that but did he ever also tell the other coworker to knock it off? Apparently that made G even angrier that I didn't take his side and ended our friendship briefly. He came back and confessed his feelings to me and that's why he acted that way. I said I didn't reciprocate it and I always just wanted to be there for him as a close friend as he has expressed he was alone here and my former friend died while she felt alone so I wanted to be there for him. He started putting limitations of our friendship and said I couldn't text him after work, talk to him after lunch, etc. I said that was pretty strict but all I wanted to do was to have him in my life but if he needed those boundaries I'd respect them. Then when I tried to follow suite he got mad that I ignored him when he looked like he needed space one day because I couldnt interpret what he wanted.
The final straw was my friend's death anniversary of my close friend who he reminded me of. I invited him out to watch a comedy show to laugh on a tough day. He ended up getting sick a week and a half before and I asked if he's still okay to do this event. He said he was. I asked him which show he'd prefer and many months ago he joked he only watches professionals. So he posted a screenshot of this lineup of very big comedians. He said these were too big of a name. I called him Goldilocks and thought he wanted to watch that one so I just bought the ticket. Then a few days later he asked which ones I wanted I watch. I said I thought he wanted to watch the big names. He said I assumed so it made an ass out of you and me (jokingly). There weren't any refunds but I said I'd just let the ticket go and buy the other one if he prefers it. He said he'd just buy the initial show that he sent then. I said I was willing to buy the ticket for him since this is my event and I just wanted a friend to watch it with. He said he can buy it himself. I said okay cool time to watch some good show, Goldilocks. He got mad and didn't text me for 2 days. I had to text back and apologize for the mean joke. He replied curtly but it seemed okay for a few days. The night before I asked if he was still well enough to go and if he wanted to go. He said he still wanted to go and felt much better.
The morning of, he texted me that he was really sick and he said sorry. Normally I'm okay with people being sick and cancelling but there were other occasions in our friendship where he'd cancel and it was because of something he was upset about and I didn't know about and he knew I hated those last second cancellations. I texted him, I get it that he's sick but I cried reading that text on a tough day like this to honor a friend I'm alone. I wanted to know if it was because of the joke or something else that made him cancel so I can just have clarity. He then got really mad and said I was toxic, guilt tripping, and distrustful and ended our friendship then.
Now I'm promoted and he's been actively telling people how he doesn't hang out with me but doesn't say why in the workplace. So our mutuals are forced to choose when to interact with us. He would ignore when I try to be cordial in the office or get in between me and another coworker's space when I was chatting with them. Then slowly icing me out with my friends in the office. Only a couple of them know and I can see them forced in this tough position so I went to him directly and I said we need to clear the air and at least not put them in a tough position. He said I can talk about work with you. Can YOU talk about only work. I said I could but he's been passive aggressive so I'm trying to open up the discussion so he can air out what's going on. He called me an asshole that day for how I handled the tickets and show, listed a bunch of grievances I never knew he was upset about and said I was toxic. I asked how was it toxic asking if there was something else going on in his life and asking for clarity if there was another reason he didn't want to go. He said the subtext of my text was that I basically said he abandoned me in a ditch. I said I never texted that. It eventually came out he was actually mad about the joke and didn't want to go. I said only wanted to understand him throughout our friendship and even now I didn't have to talk to him but I wanted to because I wanted to still understand him. I also said he's welcomed to join us at lunch because he's been isolating himself when I do go out for lunch with our mutuals. I just want cohesion within the workplace and he's welcomed there. He said he has no interest in interacting with someone like me. I said that was fine but I was telling him that to be clear because throughout our whole friendship I have always said what made me upset so he was never guessing. I never knew he had all these greivances against me until now.
After that talk he went to our mutuals to ask if this dynamic was okay and they said it was awkward at first but they just have to manage since he's adamant about this dynamic. The problem now is that he has set this separation precedent when I was trying to form unity. Now everybody feels super awkward and I can't help to feel it's my fault when my immediate supervisor told me it wasn't when I wanted to make it work but I know it takes two to tango.
My immediate supervisor knows but we haven't talked to the main manager or HR because I don't know if it constitutes a retaliation for him having feelings for me before and me not reciprocating, however I am in an upper position so he will have to report to me but he just flat out ignores me in the office and forces this dynamic weird triangulation with my friends where they feel they have to choose a side when all I wanted was to figure out what was going on. There's no way he can take notes from me without some sort of hostility at this point. What should I do? It feels super isolating.