If you've done your research, you should be familiar with the work of Dr. Sean O'Regan who, in the 70s, demonstrated that virtually all cases of enuresis, encopresis, and recurrent UTIs in children are caused by chronic stool withholding and that daily enemas resolves these problems.
More recently, Dr. Steve Hodges brought more attention to this when his DS experienced bowel impaction because of chronic constipation and nearly ended up with bowel surgery. Dr. Hodges modified the protocol developed by Dr. O'Regan (aptly named the "Modified O'Regan Protocol or MOP) which is what I did with my DS to resolve his encopresis.
We'd done multiple Muralax "clean outs" to no avail. MOP was suggested on the Kids with SN forum so, yes, I gave my DS an enema nightly for 30 days, then every other night for 30 days, then 2x a week for another 30 days. Yeah, that's a lot of enemas and no one liked it but it what was medically necessary. It was another 9 months before his rectal muscles returned to normal and we could discontinue daily Miralax.
DS is now 18 and I don't believe he has the trauma you have. As others have suggested, it's likely related to your relationship with your mother. What I did to my DS was not abuse.
https://www.bedwettingandaccidents.com/