I agree with chulita you'll be surprised to hear He won't understand why sometimes you make him go back down on his own and others you take him into your bed, sometimes you feed him and sometimes you don't.
Toddlers of 15 months don't need night feeds so long as they are getting enough food in the day. I do agree that sometimes they want the comfort of a feed, whether that be breast or bottle, but it isn't because they need the milk, it's because they need to be soothed, ie when teething or ill.
I got into a bit of a rut of giving ds2 a bottle when he was up in the night just because I was soooo tired and wanted the quick fix so I could go back to sleep. All I did though in hindsight was provide a rod for my own back. The last two nights I have gone and picked him up but not left his room, cuddled him until he settled down and put him back to bed. Last night he started to kick off as I went to lay him back down but I told him to settle down, time to go back to sleep. I asked him to give me a kiss (as I do at bedtime, to replicate the routine) and then put him to bed and said night night and he went back to sleep!
Watch it all go horribly wrong tonight now I've said that...
Trudy, chulita put some photos on fb today to show you some positives. Just thought I'd mention as I know you rarely go on there :)