I know I am making the right call but it still hurts

We have been friends for an incredibly long time like 13 years. We met when I was pretty young and hit it off we were both in a very difficult place mentally and connected over shared beliefs and several other things we had in common. He has done both a lot of really shitty and really good things for me. He helped me move across states when I was in a really bad mental place. We moved in together for the past few years after he was hospitalized for mental health issues multiple times. I stood by him even after his mental illness had him do some horrible things to me and others. I probably should have moved on then but I didn't.

Everything changed when we got a dog a year ago. The dog really bonded with me but started developing some behavioral issues. He did end up biting me but it was a one time thing and it partially my fault for ignoring his signs of discomfort. I got really attached to him and I felt so much joy and love for the first time forever. Despite his issues he is a good dog like 95% of the time. He has specific issues with resource guarding I was actively working with him. Things were going good until I got surgery a few weeks ago. The confusion of me being gone a few days and also me being bedbound and him not able to see me I think stressed him out. My housemate left out a bag of his food, something he gets nervous about. He lunged at my friend but did not hurt him. I was also upset by this that he would do that. My friend demanded the dog needs to go right away.

I ended up boarding him and initially agreed to rehoming him. I called the rescue and they basically said they could not take him in and could only euthanize him due to his behavioral issues. Another person who was interested in adopting him fell through. I loved the dog and did not want to put him down so I decided it might be most beneficial for me to move out while I see if I can work with him. I felt like this was probably the most favorable solution for everyone. My friend did not take it well, he said I was choosing a dog over him. I don't see it that way. I feel like pets are life long obligations and I realized rehoming him would be incredibly hard with his issues. I had zero intentions of cutting my friend out of my life when we moved but things changed.

He sent me some pretty mean texts about how ungrateful I am and how I do not care about him and how our friendship is over. He also refuses to assist in doing caretaking for me while I am still recovering from my surgery. I just feel blindsided by this completely, I don't think it is unusual for people to move out depending on the circumstances and that doesn't mean I don't care. I'm having some doubts if I am making the right call here. I think I am but also his boyfriend who I am also close with has stated the same thing as well. There is some chance I may still need to rehome my dog but I want to give him a fair shot.

The combination of everything just sucks right now. He was my closest friend and I definitely feel horrible about feeling like I betrayed him vs betraying my dog. Any support would be appreciated. It doesn't help I don't have many friends currently. Most of my friends are online.