Welcome. I'm glad you posted here, and hope you will come back again soon.
I'm not an expert by any means, but it does sound to me like you are experiencing depression. It's hard not to focus on the negatives when you're depressed, I know, but is there anything that brings you laughter or contentment or holds your focus for a while.....any sort of activity or personal interest that you enjoy? It really does help if you have something in your life that you enjoy doing to change your focus from the sad things that are going on. I find if I don't give my mind that break, things seem to "snowball" in there.
Have you consulted with your doctor about how you're feeling? It might be a good idea, just to see what he/she has to say, and to see if maybe some counseling might be in order. I see a therapist myself, and she has really helped me to deal with past events and my struggles with depression and anxiety. Also, if you need more information on your grandfather's condition and how it will affect your family, your doctor may be able to give you some information, or tell you where to go to get that information.
I'm sorry to hear about your family situation. It's very sad when family members are suffering, through illness or other circumstances, and it's especially tough when these things are out of your control. I understand what you mean about the fact that you still care, despite all that has happened through your childhood on up. You should give yourself a great deal of credit for working your way through university for yourself and for your niece. That should be a source of pride for you, Sadpanda, and I hope you realize what a wonderful accomplishment that is, especially since you have had little motivation or support from your family (from the sound of it). You obviously have a strong spirit and a will to move forward in your life, and I don't want you to let this depression bring you down any longer. You deserve to feel better and recognize your own inner strength.
As far as your boyfriend's concerns about you getting your issues resolved, I have always believed that healing is a process, not an event. It takes time to work through problems from the past that still affect you, and it also takes time to learn how to deal with problems in the present. I don't know if you feel this way, but I find that old issues can come up in layers......I deal with one layer at a time, and try to handle them as they arise. It sounds to me like he just wants so much for you to feel better, and perhaps he is having trouble understanding what you're going through. I'm glad to read that he acts lovingly towards you, and I hope that your time together will bring you some comfort.
Please come back and let us know how it's going. There are a lot of kind and compassionate people here who will support you.