I can shed some light at the end of your tunnel
2 pec tears, 1 minor and 1 major, both from bench pressing. 0 surgeries, LOTS and LOTS of PT, ART (active release therapy) and Graston technique.
Bad News;
I had 2 doctors tell me i would never be competitive again, let alone bench press, or have a normal looking pec. They were right, my pec looks horrible, AND im not competing because i couldn't stop all the micro tears from the volume, and bench press VOLUME is difficult
Good News;
After both tears, both same pec on Left side, 20lb DB felt heavy. I was pretty upset and down, but found ART Therapy. I cant express how awesome... and brutally painful this is lol. Within weeks of ART i was increasing weight and feeling stronger. 6 months of ART 2-3 sessions a week, like i said its painful and you will bruise and be sore, so 2-3 sessions a week is all i could handle i made almost a complete recovery as far as 1rm. A little over a year my 1rm is steadily increasing but i have had to work around the injury
Benching for Volume is a HUGE NO NO. What i had to get into my head was that i still wanted to remain strong, maybe not competitive, but i wanna be that guy that can still bench 400+ pec tear or not.
What i can tell you is this, I can still put up over 4 bills, and do not train to do so, as soon as the muscle gets fatigue , which for me is faster then the other side, i stop or changE my training. I train mostly hypertrophy now and start every workout with a fly movement and then straight to a incline movement. I do NOT use heavy weight anymore and concentrate on the muscle contraction. This is 90% of my chest workouts. the other 10% is when i have to check myself and make sure i cant still push heavy weight. those days i will warm up with light fly movements and then light incline movement and go directly to heavy bench. I will not do warm up sets as i already have blood in the muscle, and i do not want to fatigue my pec. I will hit 225lb for 3-5, then 315 for 315 for 3-5 and then whatever weight i need to prove to myself i can do. At that point its just a personal thing and to prove to myself im not getting weaker, but like i said 90% of my workouts are light and are concentration on the muscle.
I did have to change my bench technique a lot too. hands are closer inside width of the shoulders and i activate a lot of my tri. the further out the grip the more of that pec tie in you use and in my case i dont have it.. literally it tore it and balled up this size of a golf ball in the middle of my pec and we broke all that scar tissue down.
It will take ALOT of time, and with modifications to you training you will still be able to lift heavy when needed, and lift for function the other time. I can tell you this, i would feel comfortable competing again but like i mentioned i would drastically change my approach and cater it all around my tear and how the muscle feels.
good luck!