This might sound wrong but I don't want to be around my girlfriend when she's sick.
Why don't you want to be around her?
I don't want to catch her germs
While it's good you think about your own health and safety first, she is still your girlfriend. She needs you to help out with whatever she can't do, it is your duty as a significant other to help her in sickness or in health.
I've got a life to lead and I can't spend all my days taking care of her.
You don't have to spend a lot of time with her but make sure she has her basic needs met and get her food and other things she needs. I get not wanting to get sick but if you are careful you can be a good boyfriend and still stay healthy.