pay for college

I can’t seem to pay for college. I go to a Private University, and it’s a bit expensive. I have a few scholarships and grants to help me out, but it’s not seeming to help. My dad pays for my college, and it’s taking a toll on him financially! I love my dad so much, and I hate making him give up so much money to send me to college. We never really had a lot of money to begin with, but now, it’s getting crazy.
We’ve applied for 4 different loans. 3 rejected us, and the other one hasn’t even responded and that was over a month ago. I’m so confused and lost. I really NEED money for school, and even me working doesn’t help. My dad told me not to worry about it, because he’s going to do everything in his power so I can get exactly what I need. But I am worried, because what if he can’t get me what I need. I don’t want to tear our family apart with my financial inflictions!
I wish I knew what to do, but I’m going to keep trying until I succeed, otherwise my dreams will drown!