You have every right to be upset!!!! It's too bad what you are going through. Like Rohag said, any one of those issues could cause depression.
It's so sad that you lost your Dad. Don't for a minute feel guilty though. You did nothing wrong. He wouldn't want you to do that.
For right now, stop, take a breath, relax and just quietly go through your to-do list for getting back on your feet. Try to see a counselor and get some direction as to how you can improve your situation.
I'm sending all the good wishes to you.
Good luck