Serious Answer:
First few things I would do:
1. Lighten your weight reasonably, 50% of 1RM might be a great place to start for you.
2. Keep your elbows semi tucked by your side while working your chest, not 90 degrees out from your body(this will also work anterior delt, so what.) take 40(at first)-60(work towards that) seconds of your pecs being under tension to complete each SET of a chest exercise. This is VERY difficult to do, if it's easy, you're doing it wrong or you need to shorten the rest and add a few lbs. Take very short rests between sets, start with 30 seconds, setting the goal to be 10 seconds between sets.
3. Stop using barbells, period. Yes, they do work, but they are negligible if your injured.
4. No dips, period.
5. Do all pressing motions with elbows out in front, more in a tucked postion, not a 90 degrees to side of your body, assuming that's what you're doing. It's very common...
6. Stay simple use flat and a low incline, cables are fine too. Personally, I would warm up with super setting limited ROM cables with low inclines coupled with rotator cuff exercises using a 5lb DB to benchmark and increase blood flow prior to moving forward with your chest training.
Just an FYI-
Ironically, it's the elbows out form which places greater tension on the pec that creates the width and pec growth. This also stresses the RC and shoulder joint which is one common facet of many possibilities of how most RC/shoulder injuries are caused in the first place.
I would guess you love or loved dips at one point> This is a great exercise for building upper body and the worst exercise you can do for your RC/shoulder. It is rarely done correctly and almost sure to cause/irritate an injury at some point. Dips should alway be done in front of you, never behind. The rotation is too great even for the shoulder, decline presses are also mechanically incorrect for your RC/shoulder as well
Keep us posted C.