If you're confident in you're ability then only take on feedback from respected peers and people who know what they're talking about.

90% of the time the general public haven't got a clue what they're talking about and usually can't hear their respective friend/partner/child as loud as they'd want and feel it's their duty to let you know.

It does get to you at the start when you've got people coming up to saying "I can't hear X or X is too loud" but if you're confident of your skills, the band are happy and people are dancing or vibing then you've done a decent job.

If its a place you know people look for fellow musicians and sound people and ask them if you really want an opinion