You should care, and you also should give zero fucks. This is what I mean: If you REALLY didn't care, no progress would be made. You'd be ignorant to people's comments (whether they're meant to be helpful or not) and nothing would happen. However, we've all felt negatively impacted by stuttering. Mostly because of how "inefficient" we seem in social interactions. So, you should care because it adds to the fuel that you (should) already have to improve and create a better life for yourself. On the other hand, letting other people's comments consume your thoughts will burn you to the ground. Slowly, might I add. Dwelling on them is the worst thing you can do. It means you're taking your mind off the present moment and your goals. You can listen to the comments but by all means be careful about how you perceive them. Stuttering is very emotional. It's easy to lose our shit at other people's negative opinions. Maybe you were looking for a different comment than this...but take this from a guy who's been where you are and made it out the other end a fluent (and happier) speaker.