K.C.
I agree with many others here -- grief counseling may do you a world of good. It seems like you lost a very important part of your family and everyone is trying to move on in their own way.
You need to find your way.
Unfortunately, we cannot change people or make them do what we need or want. But we can focus on ourselves and although it sounds cliche, oftentimes the hardest times of our lives are the times when we grow the most.
Your father's reluctance to provide a strong shoulder for your troubles could have originated from anything, not particularly you. I think its hard for us often to remember that even though something someone may do might hurt us, they may not even be aware of it. He could be coming from an entirely different place.
You can attempt to have a talk with him, but don't have high expectations and please, don't try to demand too much from him, he may only withdrawal further from you.
Again, get to counseling, not only will it help you with dealing with the loss of your mother, but also you may find the strength and new vision to tackle the other issues that lay before you.
Good luck!