Please ignore your mother. I don't know why she's putting him first?!
I don't know the back story, but it's irrelevant anyway.
You're not happy in your relationship - you're entitled to leave
I was 24 too when I felt the same about my partner. We were living together in a rented house. We had been together 8 years. Living together 4/5 years.
I won't lie (at the time) it was the hardest thing I'd ever done and it was horrible and hard, but at the same time the feeling if freedom was great! (Even though he was a lovely guy and not at all controlling - I just knew our lives were going in different directions).
I was having nightmares about our wedding almost every night. I just knew that I had to do it, no matter how hard it was.
My parents were thrilled
His mum was very upset (she was lovely! We got on so well, she's known me since I was a young teen and we lived with her for a while, she always said I was the daughter she never had).
It'll be hard (especially now), probably for a while and you might (at times) feel like you've done the wrong thing, but if you 'stay strong' and don't take him back, you'll come out the other side if it and won't regret it.
At the time I felt 'old' and concerned about 'starting again at my age'. Now, at 52, I shake my head at those thoughts, but they were how I felt at the time! You are so young though, even if you don't feel it!
I know it's a difficult time with CV & the restrictions, but he is not your responsibility - where he lives & what he does is his responsibility. Don't be sucked in to acting like his wife or mother - you're not
Good luck - you know what you need to do 🌷