You are acknowledging it and that's a great thing. I think in some ways you have a very mature and healthy attitude about everything. I can understand not wanting to let go, so I am not going to harp on that. The one last thing I will say, and this is not to take hope away from you, but if someone leaves when you are sick, they wouldn't last anyway. You know marriage vows say "in sickness and in health". There is nothing wrong with her deciding she cannot handle the sick you (other than how badly it hurts), but it does show that she's not at a place where she CAN handle all of you, the sickness and the healthy. Depression is a hard beast to beat. Its very hard for others to stick around for. The person you need to be with is someone who can, out of deep love for you, sick with you THROUGH sickness.

Again, you have a good attitude in general, and I think you know in your heart and in your head what you really need to do. Its just going to take some time to accept it.