I aren't mentally equipped to deal with this

[kineticmagnetic]

DP and I split a while ago, he saw me through 2 years of hell mentally where suicide attempts were pretty constant and a lot of other things happened.
I have been getting help and have been much better over the last 6-8 months.
I very recently found out he is now seeing someone else and I am spiralling downwards again and feel I have no control. I tried to kill myself last week and the thoughts are constant now. It is only my DD keeping me from trying again.
How do I not let this beat me? He's just an ex boyfriend, surely it shouldn't affect me like this?

Don't want to read and run. I have EUPD, and I wouldn't react well to this either. In fact, it's happened to me and I didn't. I'm not great with issues around rejection and abandonment; I'm far more aware of these issues than I was, but it doesn't stop those horrible thought processes when triggered.
You've had a setback, that doesn't mean you're back to square one. Be kind to yourself.

Are you still seeing someone about it?

Thank you, I am still getting help, I have BPD and so rejection is massive for me. I just can't shift the suicidal thoughts.

BPD? = manic deprssive or
Bordeline personality disorder?

Borderline personality disorder

I suspected so. I prefer the term EUPD, but it's the same thing. It's such a similar reaction to the one I've had in the past. My suicidal thoughts will surface if I'm triggered by rejection/abandonment stuff; an ex finding a new partner will certainly do that, especially if I didn't instigate the breakup!
I know that BPD/EUPD emotions can be so overwhelming, it's like there's no protective skin there. Sometimes I think that the suucidal thoughts are a form of control or self-defence when the emotions are out of their boxes; it sometimes feels that it's the only control over myself that I have left when I'm very unwell. It's so hard to describe.
That's what you need to know. You're unwell at the moment; you didn't choose BPD, and you're doing the very best you can to manage this horrible condition. Personally, I have to wait for those feelings to subside themselves, it takes time though. Talk it through with whoever is helping you, whether it's a therapist or CPN.

I just can't see any light at the end of the tunnel at all, all I want is my best friend back.

I know. You could be me talking four years ago. I think the added problem with BOD/EUPD is that we're prone to forming complicated relationships. Our partners can potentially represent many different roles; lover, friend, even parent sometimes; all due to the way our brains are wired. It makes it so much harder when those relationships end. Exes getting another partner then trigger it all again.

It's horrible, and I'm sorry

Thank you, it's good to know I'm not the only one x

Today is worse, I'm sleeping constantly but it isn't restful, thankfully I have a therapy group tomorrow

I usually use sleep when I'm ill too. Sometimes it works, sometimes it doesn't.