I'd like to join Sophie in welcoming you here and can say the links she has given you are most useful, particularly the Suicide Call Back Service she mentions, who are very experienced and professional -but realistic too.
In case you are worried your talkof suicide and self-harm was OK. I tried to take my life but now am in a good place and have been for a long time.
I can see you have not lost your artistic touch, your avatar is most appropriate (and reminds me of WestWorld). You also have the drive inside to go on, or you would not be here.
Depressions fills the mind, hiding so much. I'd no idea of my likes, loves or why I did what I did, so it its no surprise that you wonder if your have lost the desire to be on stage -and work at it. Actually if you are anything like me it is all there, but buried. As I got better my old-self, likes, dislikes, love and abilities returned.
Do you think, when you are down, it is practical to simply go back to your acting environment? I used uni plus the Jane-St Theater and know there are always odd jobs need doing, lights held etc or simply talk if someone was friendly. As time when on I did more by stages. Maybe you will do a walk-on or one-liner as you find your feet again.
The groove will return, in fact I suspect it might suddenly take hold.
All of that above may not be practical, I do not know your circumstances, perhaps you would like to say. You might also like to say -if you want- what you have enjoyed and when feeling good what plans you have.
Can I ask if there is anyone in your life you can confide in? Family or friend? Someone who will be there for you, just listen when you talk and simply do nothing else but simply care? It leaves one not alone dealing with this.
My partner plus therapy and meds (plus hospital in my case) got me to a stage where things kept improving, now I'm happy and fulfilled.
You are not alone and I hope to hear from you some more.