My (48f) Mom hasn't been the same since I (20f)started dating

For context my mom (f48) and I(f20) used to be very close. We used to talk about anything and everything and though sometimes it was rocky through some abusive boyfriends and my bio father we always were very close and I tried to have her back as much as I could and she always supported me where she could.

Things changed between us when I started dating my current boyfriend (22m). At first things were awesome my mom was super excited since this was the first guy that was respectful of my boundaries and actually had deep conversations with me. My mom and I started to have issues when I started staying at his house with his roommates every so often. I always was a homebody before and I think it really startled her when I spent more time away from home. But things escalated when during my college semester I ended up really hurting my back and neck and I ended up staying with my boyfriend for a few days since he was the only one not at work to pick me up. I let my mom know I was safe but I didn't go home for 3 days. When I got home my mom was pissed and I do understand that she was scared and worried but she accused me of doing drugs and just going over to his house to have sex (I'm asexual due to a lot of trauma in my past and this really hurt me). I panicked and I know it wasn't the smartest idea but I had my boyfriend pick up some things and I stayed with him since I didn't feel the greatest and I didn't want to be berated anymore. During this time I was also really out of it and due to how my family reacted to me having to miss school in highschool due to medical issues I was afraid to go home. I kept in contact with my mom and family but I kept my distance and dealt with my medical issues and ended up taking a medical leave from college to recover.

Eventually I did move back home due to my boyfriend having issues with his roommates and he ended up moving into my room with me (after my mom, him, and I discussed it over months). We help with groceries and do chores and give money where needed for rent which I'm grateful for since it would be near impossible for my boyfriend and I to find an appointment with our current income. And although it's probably predictable my mom has been giving me the cold shoulder and snapping at me for the past few months I've been home. At one point she wouldn't talk to me because I didn't realize we were out of toilet paper and was supposed to buy some when nothing was communicated to me. And despite me trying to accommodate everything and communicate with her about the tension and how I can fix things or do better in a week or so she'll go back to ignoring me.

After everything I'm wondering if I'm the asshole for leaving the way I did and breaking her trust by not coming home right away and then living with my boyfriend on and off for 3 months? I feel like though it was rough at home if I would have stayed she wouldn't be so cold now.