Hey Droopy
I had been out of school for 17 years and I just went back this past september. I was terrified.
The best advice I can give you is find a friend. I wouldn't have made it this far without my friend Shannon. I probably would have dropped out again if she hadn't been there.
Use the resources available, use them ALL to their full potential. Greg is right, this is YOUR time to shine, YOUR dream and you CAN do it. If I can, you can. I have severe panic attacks and anxiety and I have managed 4 oral presentations in the past 10 days. I never thought I could ever do something like that. School has brought me courage, friends, and love at a time when I thought life was basically over. I now have an A+ average in 7 of 8 classes. Never thought I'd be capable of that either.

Seriously, try to find someone you click with, that helps immensely. Get to know your profs too. They can help more than you might realize. It's part of their job description to help you make it through. Use EVERY resource available, disability service, peer assistance, this forum, everything you can find to help you.
I believe you can do it droopy. I may be an eternal optimist now but I really do believe, just from your tone about wanting to make it this time, that you WILL!!
ALl the best,
Tina