It really is critical to forgive yourself and love yourself. It sounds corny and hokey, but if you are critical and lacking empathy for yourself, you will be the same with other people. The more love, compassion and acceptance you feel for yourself, the more it will spread to others.
I feel stupid even saying that, because it's precisely the kind of statement that would have made me roll my eyes in annoyance 20 years ago - but I've discovered that it's completely true. The more I forgive myself for my imperfections, the more tolerant I become of other people, and the more love and compassion I am able to express towards them. (groan! )