all of the above

i think it is more common than people realise... I don't know about anyone else but I had my fill when the kids were little, hearing of bubs who slept through from 8 weeks... NONE of mine ever did, what was I doing wrong?

It does sound as though your little boy got into an unsuitable sleep routine before his operation & as you said you put it down to how he was then..when it may have been unrelated...it doesn't mean it can't be changed but that takes time.

My DS2 co-slept until he was 14mths when I stopped BFding. We actually went to a sleep clinic, I was so over waking in the night. We fought for months to get him to sleep through and it kind of worked... in that we had some nights where he did & then he would relapse for a bit... in the end I think he just kind of did it when he was ready.

Sorry I can't offer the magic solution other than time

The only other thing is, if he will settle back down with a bottle, is there anyone who can do one or two nights duty for you? They don't have to take him, just be there to re-settle him? A couple of good nights sleep will do you good...