Nobody likes to be criticized, to be told they're wrong, but as writers we need to welcome others critiquing our work.
Do we need to listen to them and take all of their advice? By all means, no. However . . . if enough people say the same thing, you should consider it. Depending on what it is. You could have a good reason for it, and just need to make it clearer.
In a nutshell, a good critique is one where it spells out what they liked about a certain piece, the highlights and what went well (realistic dialogue, great descriptions, good pacing) and what didn't (choppy dialogue, poor pacing, not descriptive enough).
Do you know someone who reads a lot? Ask that person to read it and give their opinion. This is what I've done and it's worked out well. Asking other writers may not work as well because, frankly, they're working on their own piece and do not have the time to review yours. But if you can snag one, in exchange to critique some of their own work, do it. This is what writers groups are for too.
It's healthy to let others read what you have written, for they can give you a perspective you didn't see. I've been told I write good dialogue, but I didn't know it until it was pointed out. So, I use that as a strength in my writing, but also by not ignoring where I lack and am improving upon.