My partner is in a PTSD crisis: Survivor’s guilt, night terrors, and "refusing a future." How can I help him when he's pushing me away?

I’m reaching out because I’m scared and exhausted. My boyfriend (let's call him Shanya) is going through a massive PTSD collapse, and I don't know how to be there for him without making him feel worse. ​The Context: He has experienced a series of horrific losses starting from age 11—friends and family members dying in his arms or due to circumstances he blames himself for. He carries a crushing weight of "survivor’s guilt." ​His Current State: ​Sleep: He has almost daily night terrors. He told me: "I can't fall into a deep sleep; it's like my brain is stuck in a loop." ​Self-Worth: He views himself as a source of pain. He says: "I don't want a future," and "I will only make things worse for you." * The "Push Away": His last words to me were that I should "put myself above everyone else" and that he's essentially a "broken person" who doesn't deserve a normal life. ​Barriers to Help: He has no financial means for therapy right now, and more importantly, no mental energy to seek it. He point-blank said "No" to professional help for now. ​We’ve agreed on a "pause" until summer to take the pressure off him, but I’m terrified. I’m afraid he will block me on everything just to "protect" me from his darkness. He thinks he’s saving me by distancing himself, but it’s breaking my heart. ​My questions for the community: ​To those who push partners away: When you told your partner to "choose themselves over you," what were you actually feeling? Did you want them to stay or leave? ​To those with night terrors/insomnia: Is there anything a partner can do to help with the fear of falling asleep when professional help isn't an option yet? ​How do I stay? How can I communicate that I am staying by choice, not out of pity, without making him feel like he’s "burdening" me? ​I just want to be his safe harbor, but he’s convinced he’s a sinking ship that will take me down with him. Any advice is appreciated.