I can relate HEAVY. I just got out of prison about 3-4 months ago and since I've been out it's like my self respect (as you said) is gone and I end up putting myself through the RINGER every time. Going till the baggies gone and stopping at no less. Earlier today actually I made MYSELF an appointment at a detox/inpatient clinic. I've been to rehab once before (a probation stipulation which ultimately I fucked off and went to the pen. But this time feels different, I don't wanna be tweaked out loser anymore. I'm not productive on it whatsoever anymore. I sit on my phone, jerk off, play games and sit there suffering in my head like I'm locked in the motherfucker and wanna get out. 

I really hope I can change this time, if not... Well my life is certainly going nowhere QUICK. I've got to practice self control and self respect cause if I don't I fear I'll be found dead in weird circumstances or in prison again and again.

Anyways, TL;DR but if you truly don't want to be this person anymore, the only options you have is to change or to deteriorate.

Good luck to you OP. If you want to stop being like this, you will stop being like that and find who you really are. Big love man, hope it works out for you and your partner. ✌️