I (20m) dont know how to break up with my (22f) girlfriend of 3 years

Hi so I've never made a Reddit post, nor am I a user, but I've binged smosh so might as well embarrass myself too.

So I met my girlfriend around 7 years ago online when I was invited to a chatroom by my then boyfriend. At first I didn't really like her cuz she fought with him all the time. And others in the chat all the time. But we were all immature because if you do the math that's like late middle, early high school. Teens are annoying.

But years later after he and I broke up, and another girlfriend and I broke up, I'm actually friends with my current girlfriend. Lets call her Berry. Berry and I are in a friend group with a couple of my friends and one of their friends and eventually she just integrates fully into my friend group. All my friends like her, I like her, she likes all of them.

One day she invites me to meet one of her friend groups and after a while we realize they think we're dating. I love to flirt and she finds it funny too so we pretend that we are in fact dating. A couple weeks go by and she suggests we actually date. I'm like sure, and in pretty sure I even say sure why not. Very nonchalant. Very casual.

So 3 years go by and somehow we're still together??? I have no idea how we lasted this long. I kind of walk on eggshells when I talk to her because she gets upset at things quickly. We also don't have much in common so it's hard to talk with each other. Our hobbies are different so we can't talk too much about those either. When we talk it's usually about how her life sucks or her favorite marvel ships and I do listen and I do feel bad for her and show sympathy and comfort when she's down because I still love her as a friend, but I've communicated to her that I may never love her because that's just something I struggle with. I'm on the ace/aro spectrum but I can't figure out where yet. Love is just hard to come by for me.

I don't know if its because she has low self-esteem which sounds crazy but trust me when I say I've lived as a woman longer than I have a man and I know what Im talking about when I say that. (ftm, I haven't started T yet) For me at least, I used to stay with people I knew didn't like me like that because I wanted to feel like I had them. I don't want her to do that but its already been 3 years so I'm already screwed.

You may be wondering how the fuck we've been together 3 years when I don't love her and that's because there's been no reason to. I'm not sure her relationship experiences but from what she's told me so far they haven't been great. That's the same for me as well. I haven't been in a relationship where I broke up with them first unless it was abusive, I've always been the one broken up with. I don't know how to do it when there's no reason other than the fact being in this relationship is kind of exhausting.

I have to show love I don't have and attention I barely give my friends. I've asked her how she feels about the fact I won't talk for like a week at a time and she's like "Ill still love you and wait for you 😚" and I'm like GIRL NO PLEASE JUST LEAVE ME DON'T WASTE YOUR TIME WITH SOMEONE THAT CAN'T EVEN TALK TO YOU REGULARLY??? If I were just her friend right now I'd scold her. Unfortunately I'm the shitty boyfriend.

I want to stay because fuck do I really like her as a friend. She's funny, sweet, and going through a lot in her life so I don't wanna add any problems. Especially when she comes to me to vent about it sometimes and for comfort. She's not the healthiest mentally and I don't wanna push her over the edge or something but how much longer can this go on? When she's better, wouldnt I just knock her down again by leaving??.

I just don't know when the casual dating turned as serious as her talking about our wedding. When were we supposed to break up to stay friends? Can we stay friends after I leave now? How do I tell her now? Do I tell her now? Do I just fall for her at some point? I don't think so but my cowardlyness is saying to wait and try. But it's been 3 whole years, I don't think that's happening.

Someone please tell me how and when because we are too young to be settling.