How much do you practice and are you practicing so fast you are sloppy? Also are you practicing what Troy Grady calls "chunking", meaning accenting every 3rd or 4th stroke. It's like talking, we start having to spell out every word, then we read words as one "thing" when we see it, that's when we can for sentences with minimal effort. It's kinda the same idea, you can't play fast if you have to think of every note, you have to think in phrases.
The other thing, if you are having trouble with consistency (pick depth, hand motion, etc...) when you are just sitting around, watching TV, whatever, pick on one string (b string seems to be a good choice), accenting every 3rd note, at a speed that you can keep everything consistent, meaning not so fast you are making mistakes, start by paying attention to what you are doing (maybe without the TV), then when it becomes automatic at a reasonable speed, just keep your hand moving. It will train your muscles to be consistent as you speed up, so these things are relaxed and automatic.
The other suggestions are great too, Stetina's Mechanics books, Troy Grady's website, Claus Levin's alternate picking videos and courses, lots of roads lead to the destination, but it takes some travel time. All the guys "we" want to play like (GIlbert, EVH, Nuno, Morse, di Meola*, etc...) got there by spending lots of time.
*I don't recommend di Meola's speed technique, it is a very tense, from the elbow motion and when I watch him play (I saw him this year at the Boulder Theater) I'm surprised he has been able to play this long without damage.