My condolences to you.
I'm going through the same. We met here but spent some time together in real life, and I can't believe his gone. I knew about his plans from the start, but I guess I never believed it entirely. I miss him everyday.
I keep obsessively checking when she was last online as if she'll magically come back.
I used to do the same! I didn't want to believe it. When I saw his last post, I cried and was sad, but then refuse to believe it. Obsessivaly looked everywhere for any news about it for two days and then decided I would forget because he was probably alive. Three days after the post, I saw his friend post; "I still can't believed it". I cried so much like something inside of me was aching. And three days later I refused to believed it again. I could'nt, you know? He couldn't really be dead. He was my friend. I almost completely convinced myself that it wasn't true, that he had to be alive, I couldn't accept it. Six days after his last breath, his mom messaged me. He is really gone. And I feel so so much for her, I would give her anything if that could spare her of part of that pain. I'm so sorry for her. It's been three or four weeks, I lost count, but there is not a day that I don't think about him. It's getting easy to accept because I know it was what he wanted, he planned for months and I understand his reasons, not to mention he would be annoyed of me mourning him for too long. But it still hurts, probably always will, in a way.
I can't even tell anyone irl about her either.
I'm sorry for that, it's so heavy to handle that on our own and so angustiant not to be able to talk to someone about it. My friends are tired of hearing about him, mostly because they warned me to stay away or I'd get hurt, like I am. But my only regret is to have followed those advices in the end, because spending time with him was really great and I wanted more of that. So, not talking much about it anymore, not even to my therapist. It sucks.
If you ever want to talk, feel free to PM me.
Hope you can find comfort <3