Insomnia out of control

I feel I want to complete my life. I do not think i can carry on any more. I have had insomnia for years which is so much more profound now . I have been rotating over the counter mediacation i.e Restavit, Unisom,Phenergan and (trying not to) take S4D's.

One thought that I will not sleep....and that is it.
No sleep! Sometimes for a 48hr period then a micro sleep then nothing.

I am a shift worker with responsibilities for peoples lives.
I enjoy my job.... but feel that this sleep problem is soon going to get me sacked.

Lack of concentration and error is happening.

I have been on leave for maternity reasons but the problem still exists. Even before maternity leave I had this sleep problem. I have/am using homeopathic meds and relaxation techniques. I feel that I can no longer look after my family.