Dark Souls PTD : Had To Give Up

Sadly, I haven't played Dark Souls for a couple of months.  Not because I don't want to but because I cannot get past the dragon archers, (or one of them at least) on the walls at Anor Londo. 

I've tried every tip I could find, including removing all armour for faster rolling although I'm a Dex player anyway, and try to force the archer to go melee so he falls but I can't do it.  After 20 or more tries I got sick of running all the way there, being invaded and back stabbed, losing all my humanity only to be knocked down and fall over and over again.    I'm sorry to say I even tried a Trainer in offline mode, but that doesn't stop me dying from falls.

I've been in the Catacombs, even as far as the main Boss door which I can't enter since I don't have the Lord Vessel, and persisted through other hard levels but this defeats me I'm afraid. 

Sad face....