What's worse - taking sleeping meds to fall asleep, or sleeping with my ex to fall asleep?

If you don't stop sleeping with her, you'll never get over her. Don't cuddle. Don't be close. Don't put your arm around her, don't let her rest her head on you, don't be with her when she's gonna go to bed. Just take it one day at a time WITHOUT her, and you will start to get better. I just did this myself almost a year ago now, and it gets better, it just takes time. Just don't go back, or you'll never move on.