Try using a very flimsy pick @.38 and allow yourself to "hack" without judgement, any thing on the neck. Gradually work up to heavier picks. Its like weight training, start light high reps then work your way up. I struggled with tremelo picking for a long time, always wondering how people do it, it amazed me. There is a lot of forgiveness in a light pick and you can really dig in with it without it getting "caught, or snagged".