unhooking fish

[frogfisher]

sometimes I hook a fish right in the side of the mouth where it is really hard to get out and I try and try and try but it just doesnt come out. I dont want to hurt the fish or remove the protective slime and I heard that it is better to leave the hook in because fish develops acids that can dissolve hooks so every once in a while i have to cut the line and leave it in but I feel bad when I do because he might not eat for a while becasue of it, possibly making it sick or something but are there ways to solve htis or should I just stick to what I'm doing? By the way its not a whole lure I'm leaving in, just a hook I put in my soft-plastics