the first time he ever made me mad

i remember the first time i was ever sincerely angry at my boyfriend, like the kind of angry that i didn't want to talk to him or even be in the same room as him. i remember the day, what i was wearing, how i had my makeup done, what he was wearing. but it was a couple of months into my first semester of college. i was absolutely miserable, i cried everyday, my doctor said i was showing signs of depression, i wasn't even making an actual effort to eat everyday, i was just in a really sad place. i came home for the weekend, and ALL i wanted to do was spend time with my boyfriend. he stayed with me on friday night and the next day we spent a little time together, and my best friends grandparents were having an anniversary party, i told him me and my mom were just stopping in to say congratulations, give a few hugs and take a few pictures because it was only just across the street. we would be 20 minutes at the most, he could come with or he could stay at the house and he said he was going home to take a shower. when i asked if he was coming back, he just said his car was low on gas and he didn't want to have to go back and forth (his house is only like 10 or 15 minutes away from mine) and waste gas. I was begging him to come back because all I wanted to do was spend the weekend with him, and he just kept saying if he had clothes he'd just shower at my house but because he had to go home, he didn't want to go back and forth. I tried my best not to cry but started tearing up as I kept asking him to come back (like I said before, being at school just made me really sad) and he just said he'd see me tomorrow (sunday i was having dinner at his family's house and going back to school right after, so maybe like three hours. not exactly the weekend i wanted to spend with him). the next day when I went over for dinner, he was in the shower when I got there and his stepmom asked me if he was with me last night because he wasn't home and his dad said "no he was with brandon and all of them" which i thought he was home because he didn't want to waste gas driving to a bunch of different places, to be fair his friend lived closer than i did, but i just feel like that means you can see him any time during the week when i'm at school. and it's not really like he lied to me, i have a feeling he planned to stay home and then they called and told him to come over and he said sure. while messing around on my phone i saw he was with his friends from the day I was begging him to stay until a few hours before i came over on snapchat and was just so hurt. if this had been before i left for college i wouldn't have cared, but i just felt like i deserved that time. this was back in september. i told myself i was overreacting and never said anything, but it's been almost a year, and i still think about it anytime he mentions his friends. ever since he chose them over me that one time, i've started to resent them and any time he brings them up i find myself getting angry. ANY time he goes to hang out with his friends, even if we didn't have plans, i feel like he's choosing them over me. i don't know what to do, i can't just sit in my room angry every time he goes to hang out with his friends