Girlfriend broke up, I can't cope with it

Hello, my girlfriend decided last week to end our relationship, we've been together 4months but it felt like much more. I'm really struggling to cope with this because I'm so much in love with her and really don't want to lose her. She's the nicest and kindest person I've ever met, she is exactly what I've been looking for in someone since my previous breakup 5 years ago and right now it just feels like I've lost the love of my life and one of my only friends.

For more context, I'm 28 years old, I moved country after my previous breakup and kinda lost touch with most of my friends and didn't really make new ones since. I've been used to being alone and was ok with it, I've also always made myself clear to girls that I was seeing that I didn't want to commit, mainly because I wanted the next person I commit to, to be someone I knew I would fall in love with. My girlfriend and I met at work 2 years ago, I remember thinking how pretty she was the first. time we got introduced but later learned she had a boyfriend and were maybe gonna move together so I didn't look further and gave up, but still kept looking at her. At the end of last year, we ended up discussing a lot one evening and I learned that she was actually single, we talked a lot the following weeks and went on a couple of dates, and that's when I realized she was the girl I've been waiting for so long. The first few months together were amazing, I could feel every day my love growing for her, we were spending a lot of time together and was at least coming to hers once during the week so we could see each other more than just on weekends (I changed work a couple of weeks after we started dating so we were not working together anymore).

One evening she said she had something she wanted to tell me for a bit now: she was dealing with mental health issues for , she went through depression a while back and had a lot of personal issues but was seeing a therapist and felt better since, but she basically wanted to warn me and leave me the possibility to bail out on her before it got too serious and in case I didn't feel like I would be able to handle it. I didn't leave, the only thing that I wanted when she told me this was to be there for her as much as possible. It wasn't a situation I've ever faced before so I didn't really know what to expect but I really wanted to do my best for her.

A month later, I finally told her I loved her, and explained that it wasn't something I say a lot. I was absolutely afraid to tell her, thinking it could scare her away, but it didn't and she said she loved me too. We also started talking about moving together maybe this summer, I was extremely excited about this, we were looking at ads on a daily basis and I started talking about maybe getting a dog eventually once we would be settled.

Then, right before lockdown started, we had an argument because of the way I responded to her telling me about her concerns of her manager leaving. As he was an ex-colleague, I knew how her manager was and how little he was listening to her asking for more resources to help, so when she announced me this my reaction was pretty much "good riddance". The problem here is that I didn't realise that she needed comfort and reassurance, and I wasn't offering this at all. We talked about it and I admitted that I'm quite a pessimistic and negative person but also often think my vision of things is the only right one, and I struggle a lot to fix it. About a week later another similar incident occurred by text this time where she was in panic over a situation with her housemate and my attempts to try reassuring her turned out to be very aggressive in telling her what she should do (again because I was convinced it was the only truth). The next day when things calmed down, she told me she believed I was also dealing with mental issues and should consider talking to a therapist, and I completely agreed with her. I've always been aware I had issues but didn't think it was worth fixing them.

Lockdown started and we had to communicate via text and facetime only. It was really hard for me because I truly missed her every day, and wasn't doing much to occupy my mind on a daily basis, ending up with us having a bit of empty discussions on facetime as I didn't have much to talk about. I was starting to see her answers to my messages were different, it felt like she was slowly fading away from me so I tried to talk about it with her, to ask her what was wrong, if I was too annoying or if she needed a bit more space. In parallel I started therapy via Skype to talk about my issues, I was really concerned my behaviour would ruin everything.

Then came last week on a Monday, she sent me a first message saying she had a lot of work and might not be able to answer a lot, to which I responded it was absolutely fine and she should definitely not over-stress herself, I was really anxious about her well-being that morning but tried to carry on. About 2 hours later, she sent me a long text telling me she wanted to stop things, explaining it wasn't my fault but she didn't feel she could be with someone that also was struggling with mental health issues, that she thought about the dog situation and didn't want to have one in the end, that she thought about it and didn't think she could live with a non-vegan (I was vegetarian but have now just started being vegan). She said she sent me this right before my therapy session because she knew I would be able to talk about it then, and if I wanted to talk about it after she would be ok but that her decision was final.

I was in complete shock and panic, the therapy session helped me a bit to calm things down and think about things so we called each other right after via facetime, but then it just all came back. I was in complete panic and pain, I couldn't calm down, couldn't talk, I just kept crying and decided just to stop the call. She kept texting me because she was worried about me, but I still couldn't calm down and my whole body started to feel numb. I saw a knife in my room and just started slowly cutting on my wrist, I didn't feel anything so I kept going. She kept texting me and was worried I was hurting myself, to which I told her I was. She then texted my housemate to check on me, and feeling ashamed I just hid the knife and stopped, trying to calm down. The next day around lunchtime I sent her a long text responding to all the points she brought up, trying to tell her I just wanted us to talk about this, that I really wanted to change and be better, that I just wanted us to call at the end of the day and discuss it again. She answered her decision was final and has nothing more to talk about, then blocked me. When I saw she blocked me I just completely broke down, it didn't only feel like losing the person I was in love with anymore but also my only friend.

Later the same evening she unblocked me, explaining she just couldn't focus on work because of me then and had to do it, to which I apologized and told her I would leave her alone from now on but was here to talk whenever she was ready to.

It's been a week since and she hasn't talked to me. I've been trying to do things to focus on myself, changed to a vegan diet after watching a lot of documentaries on the topic, completely cleaned my room and implementing back some rituals I had like morning exercise, etc. But even though I'm trying to focus on other things, at least 2 or 3 times a day I just have those panic moments where I will think back about good memories with her, followed with thoughts of her not being with me anymore, or her finding another guy, or never talking to me again, or never being able to win her back, and I can't control them and break down in tears.

I'm struggling so much to accept it, all I want is to be able to talk to her and tell her I will leave her as much time as she needs, that I will do everything to make it right, but that I won't give up because I'm so in love with her.

I really can't lose her, it hurts so much to think about it.

I'm sorry for the really long message, hope it didn't discourage people from reading.