I never ask friends and family because you know they are gonna say they like it even if its crap
lol, my friends and family tell me what they really think most of the time. I guess it helps though that most of my friends are designers, lol.
The first person I ask is my girlfriend usually since she’s near me most of the time doing homework or something. It’s fun when I ask her because she says, “I don’t like it.” I’ll ask her why and she’ll say, “I don’t really know but something is off and it needs some more work.”
lol, all I need to know is that some people think something is wrong with it and I can usually figure it out myself or with the help of other designers with “fresh eyes”.
As simnor said, Twitter and Forums of other designers/developers that engulf you in the industry, provide valuable feedback and create great connections/networking will make you better at what you do. 
jremick is an Envato staff member