I need help!!!

Okay, ever since I was about 4 months, I've been suffering from back and hip pain. The further along I get, the worse the pain becomes. Right now I'm 32 weeks and the pain is so bad that I can't sleep and I wake up every morning in tears. The pain starts in my lower back near my tail bone and radiates down into my hips and my legs. Some days I can't even walk. I also get terrible groin pain and it's hard for me to get up if I'm sitting or to sit if I'm standing. I bring this up at every OB appointment because my job requires me to do a lot of standing, walking, and heavy lifting, which is becoming difficult due to the pain. My doctors tell me that this is normal and that I can't get a light duty note for my job because there is nothing wrong with the baby. And I'm becoming frustrated because I've tried stretches, hot showers, hot baths, Tylenol, massaging the spot, and getting a belly belt, and none of it works. There is a physical therapy place but my doctors won't give me a referral to go. (And I need one to go to this place) I'm trying to tough it out, but I need to work and I feel like I'm going to get fired because I can't do my job and I'm just freaking out and becoming really depressed. Has anyone experienced any of these symptoms and found something to help? I'm really desperate since my OB doctors won't listen and my primary care doctor doesn't want to go against my OB office. I really don't want to lose my job and I'm trying to work up to my due date since I only get 6 weeks off.