Dipper, man... I don't know what to say other than I can sympathize as I've lost a few close friends before and know how hard it can be to adjust. I am really sorry about your loss, but my mom told me something that stuck with me when her best friend passed way from cancer, as well. She told me that she didn't regret that their friendship had to end that way, but she was grateful for the memories they made together. I'm not sure if that'll help you now or a bit later when you start to recover, but know that for what time your friend had, you were everything she could have ever asked for in a friend. 

As for this old ship, don't you worry about it and take the time you need. We'll keep Zainat around, even if he's doing behind the scenes stuff, but as soon as you're ready to come back, we'll keep your seat warm. You'll always be welcome back here, and I'm sure the rest of the gang can attest to that. You're a good guy, a great friend, and I am terribly sorry you're having to endure something so wretched. We'll be here for you, man. You take all the time you need. I don't want you feeling like we're going to get rid of your spot because of a personal tragedy, that would just be shitty.

We'll be here for you when you're ready to return, okay? You do what you need to do, and if you need an ear, don't hesitate to get a hold of me.