I'm pending my 2nd knee surgery

I’m pending my 2nd knee surgery. Not a choice because of my locked knee… 5/2019 I injuried my knee. I had a complete tear of my ACL both bundles, PCL tear, & LCL tear, non-depressed lateral plateu fracture posteriorly… 1st surgery was to repair my ACL using a donor allograft graft. However in 2020 I was standing up from the couch & felt severe pain almost more painful then 2019. All I was doing was standing up. MRI was done & a new horizontal tear medial posterior horn & calf strain showed . My PCL is unchanged… Here is my question. I wonder if the MRI didn’t pick up my torn meniscus in the 1st MRI. I question if my PCL & LCL should have been repaired? I trust my doctor but starting to question my 1st surgery. I don’t want to have to have another surgery monthes later… 2 & done… Im trying to lose the weight I gained from my ACL surgery & get both legs strong enough for surgery. Definitely taking my time but today knee gave out on me & I worry about injurying it more… Why did my Meniscus tear from just standing up? Has anyone had a surgery on the LCL & PCL? Any surgeries on IT Band? The doctor feels my IT band is why I have pain on the outside. But nothing is stating in MRI about my IT band. I just want my life back. How did u get your knee back fully?