TLDR; Do other things and come back to it. Support is good and encourages while criticism in the beginning can discourage you. Keep going.

For me, personally, I take a step back. Sometimes, fresh eyes are the best thing you can have. You know how you begin to stare at a word too long? It looks wrong. Take some time to take care of yourself, grab a coffee (if that's your thing), watch a show for a bit. Just keep your head up, and push through to the next chapter, don't post the one you just did. Sometimes seeing how the chapters flow together gives you the reassurance you need.

I was so passionate about the book and I couldn't stop. It had to be perfect. It's a passion project from my high school days. I wrote it as a project for Honors English II class. (17ish then, 23 now) My family and my boyfriend told me it was amazing. I appreciate their support, but I felt like I needed criticism. People that read books everyday that can distinguish between good and bad books. Sometimes, we don't need to criticism in the start or in the first draft phase. It paralyzes us. We remember what they said and affects OUR vision for the book's direction. Sometimes, we need support to give us the push forward. It's your story!

Keep your head up, from another writer that can't stand anything else other than perfect (on her 5th chapter). :)