You mentioned that Virgin Media is very expensive....
You can get a 50mb connection from virgin for £25 a month on its own.. a landline is not required and if you take more services like telephone and TV with them you will find you can get a nice deal with them...
The cheapest I think I've seen FTTC for is £30-£35 per month as you will require a landline.
So Virgin will either be the same price if not cheaper.
If you get referred to Virgin media you will also get free installation and a friend will get £50 off there bill..
I would be more than happy to refer you if you don't know anyone already