LDR trouble

This is my first time reaching out for help, simply because I don't know what to do. Here's the situation: I have a grilfriend since 6 months now, we met online and it didn't take long at all for us to fall in love with each other. We have always been very open about our problems and can talk about anything. We love us so incredibly much, we spend hours every day writing, video chatting, or doing other things together and we both are so very grateful to have each other and our love is the purest thing we ever felt. But here's the problem, I knew from the very beginning she had social anxiety disorder and sometimes has to deal with depressions. I support her the best I can, give her time if she needs it, am there for her if she needs me and I can deal with this. Since she got to know me she made a lot of progress with pretty much everything, handling life. So everything between us is looking wonderful and we both want a future together. For that we finally want to meet even if just for a week, but exactly that's the problem. My parents don't approve of this at all, they are worried about me and my future, about always having to adjust my life to her problems and I can see what they mean, but I would be fine to do that, because our love is that strong and I'd do anything for her. I had many and long talks with my parents, trying to convince them, but they are not going to support my relationship, they even go so far, that if I choose to visit her like that ( about 450 km and different country ) they would cut off every support they give me besides financial one for my studies. Our family relationship is suffering a lot from this, but I would be willing to accept all of this for her, for a life with my girl. I know many people say that with 20 you are a grown up guy and have to decide what's good for yourself and I can also see that, but I don't want to lose my family like this and if they keep restraining me like this I think it will be unavoidable. And yes, I have to visit her, she simply can't visit me the first time, because of her problems, though she tries so hard, that she even agreed on meeting half way for each of us ( which really is a lot to ask her for, but she would do it! ) Though she couldn't stay over night in a hotel, so she wants us to spend the day in that city and drive back in the evening with me to her place, because this is her safe place, where she doesn't have to worry about the outside world. It's hard to really form a question for this, but I think it would be family or the girl I am truly happy with. I have to add this, I know family always only wants the best for their children, but they don't see, that she is the best that ever happened to me and that I need her to be happy. Thanks to everyone in advance, I really need some tips or opinions from people not involved in this.