Feeling Like The World's Shittiest Friend

This is probably one of many times I've hurt my friend. I have a friend who is in a wheelchair. He got paralyzed in a car accident when he was a teen and we were friends before he got paralyzed. Childhood friends. I'm a CNA so I know how to help him if he needs help. I've changed his diapers, helped him up the stair, stuff like that. I'm in nursing school and started seeing this guy. My boyfriend doesn't really like my best friend and said he can't keep up with us. He also doesn't like that I've seen his junk. I explained that no one is getting turned on from a diaper change. It's strictly work for me, and he's always mortified when I do it. Anyway boyfriend just didn't like him so I kinda started spending less and less time with my friend. Then I started ignoring him. It was just me being super shitty. Ny boyfriend would talk about him to his friends. At first I just ignored it, but then I started joining in. Again... being a super shitty friend. We were all hanging out at his friends house playing beer pong and again we were all talking about him. I wish I could say I was stupid drunk when I said what I said, but if I'm being honest with myself I was just a little buzzed. I just said so much personal stuff about him. Idk why. I wanted people to think I was funny and fun to be around. It was really embarrassing and really personal stuff. A few days later, best friend comes by my house. Someone from my boyfriend's friend's house told him I was talking about him and some of what I said. He yelled at me saying that if I just see him as a job and not a friend we shouldn't be friends anymore. He started getting emotional which made me get emotional and he said I was the only true friend that stuck around but he now sees I don't actually care about him. He left even though I wanted to talk it out. My boyfriend said I shouldn't feel guilty and that it's better this way, but I care about him and am finally realizing I fucking suck

Edit: I know everyone is blaming my boyfriend but it's not the first time I have done something shitty to him. As hard as this is to admit its also not the first time I told his business. You can probably find the post I made about that a long time ago somewhere on here. I chose to do it. No one made me. I can be a shitty person and I need to change that.