how can I leave lomotil?

Good thing that you have decided to stop it. But let me be very direct: withdrawing alone from lomotil is very dangerous with high risk oof return to drug use with even fatal overdose. I'm being very direct because that's a serious situation. go for a residential treatment, you will have medical, psycological support that is really necessary. There's no proper treatment that can be put into words here, first because we don't know how much you take, second because we don't know what symptoms you will have when you start to take it out. So really, don't do it on your own! Look for professional help! take care!