Hi Caz - sorry to hear you're still struggling - but well done for keeping at it. One thing a friend of mine suggested to help my ds start learning night from day was to take him out for a walk during the day. Not sure how it's supposed to help.. !
I also use a low light in our bedroom, with the switch within reaching distance, so can switch it on when feeding/changing and then off again when ready to sleep. Sometimes the light stays on all night (when I fall asleep!), but as it's low and 'different' to the main light/daytime, it may help... ? And we don't talk (unless ds is upset, and then I quietly shush him to calm/reassure him).
I think it's working, as he's sleeping better, and bedtime is the ONLY time our ds will lie flat on his back whilst awake (he's a very active little chap, and hates being put down anywhere... )
I did also give our ds to my dp for a while during the night when things were really bad and sometimes he would quieten down once he was away from me and my milk..! Not often, tho...
I've also been using my iPod when he has a bad night - just helps to pass the time (being a complete saddo, I load it up with episodes of the Archers and Women's Hour but, hey, anything's entertaining at 3am!!)
I really do feel for you, but it won't last forever. xx