I know you don't want to admit this, because you probably feel like you are weak or have something that you are fighting with your ego - but the people saying you should drop the weight are 100% correct. Start with the empty bar and get full reps. And don't just drop the weight, do a full rep and then say, "now let's see if I can do it with 10's on there?" - Just focus on the form. Your body has to learn the movement just like it needs to learn how to shoot a basketball. Practice the movement, not the weight.
You may need to do 1,000 reps before this movement becomes second nature. Do an empty bar - do 5 sets of 20 or 4 sets of 25 with PERFECT form. Then, the next week go to 55 and repeat. Then the next workout, add another 5 pounds. Do this for 10 workouts and you will be doing perfect sets with 95 pounds. At this point, the movement will be close to second nature, and you will have begun to build up your supporting muscles so that you don't have the same issues. The rotator cuff exercises could be good advice too.
After you do this, you will be ready to start lifting the heavier weights. Or you can keep banging your head against the wall trying to bench heavy weights that you can't move effectively, and that are hurting you and creating a potential for injury.