'When she shuts down and starts answering your questions with one word answers, stop engaging her! Tell her that you look forward to spending some quality time with her and when she is feeling better to let you know, and that you'll be in the living room reading (or whatever). I know that will be hard, but you said you want to help. Helping will be hard. Fact is, the relationship may not survive this issue, but I think it has the best chance of surviving if you set some firm boundaries around this. You are NOT going to chase her around begging her to talk to you. You are not going to behave as if you are uncomfortable. If she insists on being bad company, you will keep your own company - or even spend some time with other friends (granted that might be hard in a LDR cause you're probably getting together just to see each other)."

I appreciate the advice. It is hard, however, because it is a long distance relationship, so all we have is our emails and phone conversations. If she's like that on the phone and i disengage her, then I don't get to talk to her that day. If she's like that in person then I'm kind of stuck with her for two days. It's also tough because if we are on the phone, literally everything can be fine and then all of a sudden she'll shut off so it's hard transitioning from being great on the phone to talking to someone who is not talking to you. I hate when I have to say "Is it everything okay? Is there anything wrong? I know something is wrong, just please tell me and if it's something that I won't like I will not be mad at you and we'll work through it together." I hate that line of thinking because honestly it depresses me. Obviously being sad is a normal part of life and if she was sad literally every day but she told me why and it was something we could work on together or atleast something I could help her with, then that would be a lot healthier for me. I'm fighting a problem now that I can't help her with and I don't even know what the problem is half the time.