trying to survive NC after 3 years

just to start off ik everyone is going to say i am better off or i deserve better or how everything is going to be ok but after 3 years of constant understanding, support, compassion, empathy and love. i (25m) was told that they (27m) would never love me unconditionally and that the relationship was “toxic”. ended the relationship and chose drugs/alcohol over me. i knew of their problems and still embraced them with open arms which could be my fault for being so naive. i feel like the relationship was sabotaged/ not supported in some ways because of their addiction issues/cultural and sexual orientation but i could just be in the denial phase of grief rn. they are a product of their environment and will most likely continue to fall victim to repeat the same cycle because they are enabled by family and even the “therapist” and i will continue to pursue my dreams and talents. it ended so abruptly and apparently they changed their mind in 2 weeks after 3 years of planning out future together, constant talks of growing old, living together and etc. i’m blocked on mostly everything (insta, messages, telegram but surprisingly not reddit) but i see they’ve been following ppl they used to know or “talk” to on social media…which really hurt but they’ve used that excuse before to catch up on old “friends”. i reached out yesterday left a voicemail to talk so we can end things on good terms but i don’t think anything will come from it. they are not mentally in the right headspace and has been drinking on antidepressants and other meds. i realize that two things can be true…they really did want to plan a future with me and he was the most sincere and genuine person and i believe him but at the same time i have come to realize the will for addiction issues stronger. he cries and talks about him done ruining his life and hurting the ppl around him but continues to fall into old habits. they might see this post but im done deleting and hiding. i have constant anxiety and ptsd from this and i have to let go of whatever happens to them because it will not be my issue after all i’ve done to get them out the hole. after everything i am still so in love with him and i genuinely hope that i can still have a future that we planned but i am not ok. i am trying to be but i know it will take a while. i hope i can be strong enough to see it through.