I don't have any other solutions but to try and wean him off nursing to go to sleep. I went through a simila thing with my son around the same age. We had just been on a 5 week holiday and he was terrible when we got home. I ended up feeding him and regardless of whether he was asleep or awake my DH put him to bed.

In the end also I had to let him cry. I hated doing it but I had to. I wasn't coping with the sleepless nights. Maybe you might have to do that as well.. I was surprised how quickly it worked. I didn't do control crying I just left him to cry. Now I know that sounds horrible and believe me I felt so mean. I did check on him and make sure he was ok but I refused to pick him up or feed him. It took about 3 nights and the night waking virtually stopped