You listen to me. God has not put more on you than you can handle - He promised never to do that. Your faith in Him may falter, but His faith in you will not. I know you are hurt and scared and mad and frustrated and it's okay to have those feelings. It's normal and healthy and you are doing it just fine! As for your marriage. This is really going to be a trial by fire for that. I agree with counseling, it helps but may not fix anything. You are the only one who can and only with God's help. So go ahead - scream, cry, bawl, curl up and sleep for days if you have to. Then, get to church. Find a group to take you in and get on with living. God will help you, He already is helping you. Forgive yourself, if He can forgive you, you certainly shouldn't think you don't deserve to be forgiven. Understand that what you grieve is your time with your beloved sister. It's okay to miss her. Give all that sorrow and stress and hurt and anger to God. Let go of it. Your sister is no longer in pain and never will be again. You're the one in pain. SHE WANTS YOU TO BE HAPPY. Do it. Do it for her, and do it for yourself. I wish your husband were better able to help, but he is having his own issues at the moment, and you are in no position to help him. Find someone who can help you both - in the way of a Christian counselor, pastor or church group. Pray for your DH twice a day, it is hard to be angry at someone you are praying that hard for. I, and many others, no doubt, will pray hard for you. Remember your promise, to love, honor and cherish, for better or for worse, in good times and bad. Love is a verb, it means that you are doing something, not feeling something, and it is not dependant on the other person returning it equally. Forgive him, even when he doesn't deserve it. It will be better for YOU! God will bless you for it. You will start to feel a little stronger as time goes by and eventually you will realize that you are going to be alright. You have God to lean on. You have his strength inside you, it's just hard to find right now. Keep looking for it and show it to others when you can. God loves you, your family and friends love you, I love you. Love yourself.
Now, I understand the anger others have expressed toward your DH. I feel that, too.
Ya'll don't jump all over me about cutting him too much slack. I'm not saying he's right and I am fully aware that it may get worse before it gets better. Her marriage may not survive all this, but our sweet OP can not do both parts, she can only do her part and the rest is up to God (and her DH.) When she has a grip on her own turmoil and she is strong and thinking clearly, she will be better prepared to deal with the issues he has that all of us see.