Well, having experienced this with our DD1, I would say that you have to be very determined and also in agreement with DP (if you have one).
DD1 was 13 mnths when I decided enough was enough...she had started sleeping with her arms wrapped around my neck all night!!
I went along the controlled crying route, laid her down in cot after bedtime routine (which I think is worth getting if you dont have it already, eg bath, teeth, story, song, goodnight, you leave). Returned every 5 or so minutes to pat her and reassure her.
I wont pretend this was pleasant, however I will say it was worth it to have a decent nights sleep (for both of us).
TBH, it took only a couple of nights for her to settle quickly, but she cried every night for about 3 or 4 minutes until she was about 2. I think it became a part of her routine!!
So, good luck, I hope it works out ok for you. I have DD2 who is 5 mnths, and also co- sleeps, so will be repeating the experience again in a few months myself.