Useful feedback isn't the same as assurance or validation, even though all of them are helpful in some way.
Useful feedback often feels uncomfortable because it helps people learn something new, and learning something new or making a change can feel uncomfortable even vulnerable.
Useful feedback often makes us want to run away for good (but don't). When feeling disconnected (uncomfortable, pissed off, or upset), connect with ourselves first. Come back and internalize the feedback. When we give it a chance and calmly think about it, we can go further with these two questions: How can I apply it to my project? Does it help me move in the direction I want to go?
You will know when it's selfish feedback which is from someone to satisfy their needs and egos. But you will also know when it's useful over time.
If you have received useful feedback, please thank the person who offered it to you. This encourages them to keep doing what's working. When giving and receiving useful feedback is a norm in a community, that's something worth remarking.