Signature and writing phobia. Helps.

I have anxiety problems since intermediate. I'm aware of it and am able deal with it in most of the situations except one, which is while writing especially when other people are present. My hand shivers while signing any document and the problem is worse when i'm in queue. So the first thought that occurs to me in any activity is if there is a signature involved. Hence, i'm avoiding applying for a driving license, passport etc where I have to stand in queue and sign a document. If this is unavoidable I just write my name slowly letter by letter shivering and the person looking at me is always surprised. I was depressed and left my job 2 yrs ago and stayed at home most of the time avoiding everyone. Now I'm confused about getting another job. For last 3 months i tried planning a list of daily activities to change my behavior and it is making me more active. But I'm not able solve this one phobia. i tried physiotherapy, read self help books, but when i'm around someone nothing helps.