You did not cause this You cannot control this You cannot cure this
Ex's are ex's often for good reason, particularly so in your case. Its more than fine to walk away from such a situation; you are in no way qualified to rescue and or save them from themselves and I mean that most kindly.
I don't know why people think you shouldn't walk away. That you should always help.
Possibly because that's what they've been brought up to think, in a family which is either a) normalising addiction or other dysfunctional behaviours and that it's your role (especially as a woman) to just constantly look after others, or, b) their family was so functional and healthy that they cannot conceive of reaching a point where for their own sanity and safety that they have to walk away.
I was brought up with a) and it's taken me near on 40 years to realise you don't have to just shut up and keep taking shit.
i know how you feel my ex did not have an addiction when we were together he developed one very quickly after we split i tried to help (we have a child together) then i stepped away he went on to remarry have children and still have an addiction his wife blames me for everything she sees me as weak for not staying with him not "standing by my man" she thinks its her right to abuse me because of this because its all my fault he does not see his child of course she also has an addiction but its okay because she can handle it and they put the kids first always (when high) and are brilliant parents unlike me the deserting slut
you cant reason with people in the grip of addiction
i wish i had found this thread earlier before i unblocked her on facebook to ask her to stop slagging me off in public making vile accusations on facebook to be read by my daughter as its upsetting her i should not engage with it all but really.......