I've not felt like I've been living 'my' life since the breakup

7 year relationship, split in Feb. For context I'm 28 so that is a quarter of my life so far. We've been no contact, we don't have each other on social media

I've not felt right since. I've been dissociated. I feel like I'm watching someone else go about their life while I just watch. No one and none of the places are familiar. It's complete and total derealisarion/ depersonalisation. I've been seriously depressed and I'm genuinely not sure how long I'll be able to go on like this. Im just at a stage I don't care what happens to me lol. It's not even that I've lost her, it's just the total change in my life. I pretty much feel like there was an old me who died if that makes sense at all. I look different in the mirror, feel totally changed in a bad though (dispute outwardly being fitted, more successful). I don't know if I even miss my ex anymore tbh, it's all just fucked