I had insomnia throughout pg just as you described. Toward the end, I used to listen to relaxation cds or other music cds to switch off my brain. Usually I would fall asleep within a few minutes of starting those. Also hot milk with vanilla was nice. I didn't think of Horlicks. If you think it would add to the problem though, it might not be a good idea for you.

I also have a relaxation exercise I read somewhere when I was about 11 and I still use it now. I think it works because you focus on your breathing and it takes your mind off whatever is worrying you. It sounds a bit stupid when it's written down but it absolutely works for me.

Picture yourself on a swing going slowly back and forth. Say in your head "sleep, two, three, four, back, forth, back, forth" breathe in, breathe out, breathe in, breathe out.

As I said, sounds stupid but it beats counting sheep and it seems to work well.