You've found the weakness in your game, now its just a matter of figuring out how to make a correction. I'll explain an exercise I've used that has a threefold benefit. It will sharpen your timing, your familiarity with receiver routes, and help you make the throw you need against the coverage you're facing.
First, forget about the defense. You need to set your internal clock to know when to throw while timing up your routes with the steps of the QB. Go into practice mode with OFFENSE ONLY. Pick any pass play.
While on the field, utilize this time to hot route each receiver to a different route to familiarize yourself with all the options. Slant one guy, hook the other, streak someone else, and block with a back... When you play, you will need these actions to be instinctive. This exercise will help.
Once you've hot routed and feel OK with it, it's time to take a snap. On the first 10-15 snaps, don't throw the ball. Just look at the QB's feet and count each step OUT LOUD. When playing, you will want to be ready to throw on your 3rd, 5th, or 7th step. This will set your internal clock and help your progression.
Now that you have the timing, it's time to throw some passes. Start with the Hook route and take a 5-step drop. Throw the ball without any stick movement and you'll notice that if you plant and throw the ball will be in the middle of the receiver's chest as soon as he turns.
Now work the ball AROUND the receiver. Imagine a defender in various positions and try to use the stick to throw away from him. You'll notice that the ball isn't thrown at the receiver's chest, but out away from his body in the direction you choose...
Do this with several other routes. Experiment with throwing these routes on 3, 5, and 7 step timing. You'll find the sweet spot so you deliver the pass just as the receiver comes out of his break.
After a while, you'll be so accustomed to where the routes break that you won't need to look at the receiver to deliver the pass on time. You'll find yourself reading the defense instead of staring down receivers. Then you just throw away from them just like you did in practice.
Hope this helps,
Later