You'll think I'm weird but I'm 25 and I still cuddle a soft-toy at night.
That's not weird if it is something that brings you comfort?
I have a strong positive association with that soft-toy, it reminds me of my childhood
If is something that makes you happy, there is no need to be ashamed of it. I understand wanting to hang onto stuff that connects you to a happy time of your life.
My mom thinks the toy is disgusting and tells me it isn't right to still sleep with one.
Don't let other people talk you out of something that brings you comfort and doesn't harm anyone. Just because your mom things it's gross doesn't mean anything, cuddling a toy is innocent and perfectly reasonable.