When brain-computer interfaces are perfected our minds will be networked with computers and each other. The concept of privacy will seem very quaint to or children’s children.
Resistance is futile.

Honestly, if you’re that easily discouraged, maybe you should give up.
Ask yourself, are you passionate enough about telling stories and creating comic books? If this is your first comic book it probably won’t be very good. If you want to become a good writer you need to put in the work. Finish this graphic novel, reflect on what did and didn’t work and make another one, and another and another.
Even if you do become a good author eventually, chances of commercial success are very slim. For every writer that succeeds, there’s a hundred who failed. At the end of the day, the only thing that keeps struggling artists going is sheer love of the game.
Do you care enough about this story, that even if only your mom and a handful of other people end up enjoying it, it was still worth telling? If not, then you’ll never make it. If you do, then you probably still won’t make it.
From what you told us, your friend doesn’t sound like a great friend or critic. What is stupid about it? Why would that stop people from being interested? Even stupid things can be very entertaining. Evil Dead 3: Army of Darkness is very stupid, but one of my favourite movies. Ask your friend for some constructive criticism or just ignore them.