Depression and Anxiety

Okay. So. It's been going on for awhile now and I'm really freaking out. My friends broke up and her reason was that she just had a feeling that he wasn't the one. And I've been freaking out about my relationship ever since and that was in September. My anxiety and depression have been getting worse and worse and I can't tell if that's causing problems in my relationship if it's my relationship making my anxiety and depression worse. I just want to vomit and things getting getting worse. He's my best friend and I thought I loved him and we were perfect together but I'm in my head all the time and freaking out about everything and I just want everything to stop. I hate college and existing. I'm going to a therapy consultation Friday but what if my relationship problems are the cause and we end up breaking up because of that. I can't tell what's real and what's in my head and I don't know what to do. Does this happen to any one else with anxiety and depression? I'm so tired and scared and sad and anxious and I just hurt. 
And he's been nothing but helpful and understanding and I feel so bad that I just can't see a future right now because I can't even see my own future. I can't imagine being truly happy again. And it hurts so much because I know I have to make the effort to change but I just don't feel up to something so difficult right now.