My DS has always fed to sleep. I didn't mind. I've always said I wouldn't leave him to cry in his cot a d have never seriously entertained the idea of sleep training. I breastfeed on demand when he wakes and was happy to let him do his own thing in letting his sleep patterns gradually lengthen etc.
In the last week, DS hasn't been feeding to sleep, as he has stopped feeding and just bites, which is his indication he is done! I've tried to rock him to sleep instead (he doesn't normally rock to sleep before bed, but will do at church, out and about), but he's not having any of it and just pushed off me if that makes sense.
He's clearly so tired but won't be settled by me. The other day I thought I'm in it for the long haul, so I put him down in his cot while I went to the loo and made a cuppa to take back up. He was whingy crying but not distressed crying. After 10 mins, he'd sent himself off to sleep. The next day, similar but with some slightly more urgent sounding cries, but not awful/distressed. I had to leave him just a few minutes as I was just finishing up cooking dinner, but then he settled himself to sleep.
Putting him in his cot seems to be all that works at the moment but it completely conflicts with me not wanting to leave him to cry, not wanting to sleep train and comforting him with boob.
Tonight he just wont be settled - he won't feed to sleep, cuddle to sleep, be rocked, but is sounding more distressed than the last few nights.
It scares me that when babies are sleep trained, they just learn that no one will answer their cries. I don't want DS to ever think that I'm not there for him 
I'm at a loss how to settle him when nothing is working right now, other than putting him in the cot
Please help with your suggestions! But please also be gentle, I have PND and anxiety 