Need help in a deadend situation

Me and my girlfriend have been in a relationship for almost a year now. We are both 18. Soon i will be joining the air force and she starts college in august. Half of the time we spent together was long distance but since then she has moved back to my state and things have been going great. Except one thing. Her parents do not like me whatsoever. My girlfriend deals with a lot of stuff. Depression and anxiety being the main thing. And she is very strong willed. However her parents think that somehow i am feeding into her depression and digging her into a deeper hole. This, as my girlfriend can attest for, is totally false. I have been 10000% loving and caring for her in this entire situation. We have had our differences in the past but we have put that behind us. Now her parents say that if she continues to date me she will be kicked out of her home. We have resorted to dating in secret. And with our luck we will be caught sooner or later. I love this girl with every fiber of my being and thats why i havent gave up on our relationship. I dont want this kind of relationship with her parents. Nor do i view them as the enemy. I want to turn this whole situation around. Does anyone have any advice?

They think i am feeding into her depression and anxiety somehow despite being nothing but a positive aspect in her life. They fail to see this