You have a lot of stuff going on there, now some of it is warranted, yet some of it is just not your responsibility, even though it feeling like it is, so what you have to do is put your self first, if you place yourself in a position of strength, by looking after you and taking complete responsibility for your life, then being able to help your family will happen in a way that works well for you, on your terms.
If you was to close your eyes, and play attention to what is happening inside your head, you will notice, that the only person, in there with you is you, if you was lost an a highway in the middle of a dessert the only person with you is you, even thing else that you carry with you are your thoughts and emotions,
So you know, what you can and should do, and you know there is nothing you can do about, what has happened in the past, and all the baggage that you have with you is from your past, grieving is an important process, yet there are two types of grieving there is the type, where you remember the good, times with that person, and you celebrate their life, then you let them go, and say good bye, yet knowing if you even need them, they are in your heart. Then there is OH my AAAAAAAARRRRRRRRRR what am I going to do, type of grieving, where you give your power away, and start making excuses not to function well in the world, and that needs dealing with, and one way to deal with it is to get out all the family photos, bully every one in to in kitchen, or some other room where you can be together, and remember and say good bye together.
Then tell every one, that they will do something to make a contribution, even if that means some one reads the news a granny.
I would recommend Resiliency: The Key to Surviving and Thriving in Today's World
Al Siebert, PhDhttp://www.resiliencycenter.com/albio.shtml
I got the audio book from learning strategies awhile back have it is one my most treasured learning tools.