That is the cycle of life. Grow, age, and leave. This is where a certain principle becomes quintessential: Sometimes we let other external factors, be it people or situations, slump us forward, and weigh upon us heavily. How so? We live in a critique-happy world, where everyone is ready to offer an opinion about someone or some thing- be it system or product. Living up to everyone's ideals can be a sure way to overload our being and drown in unhappiness.
True, there is always something we can work on, tweak, modify, edit. We move forward endlessly striving to be a better person than we were yesterday. But we can't let anyone that sometimes even with good intentions squashes our entire paradigm by making us feel "not good enough." The reality is we all have flaws and yet we all have qualities, and if we work hard on sanding down our flaws, our virtues shine brighter. But that is not to say we have no value- even a crumpled up $100 bill is still worth $100, and no one would hesitate to pick it up if it was stranded.
So if someone has made you feel incomplete, flawed, or simply inadequate- don't let it get you down. As long as you acknowledge your faults and strive to buff them out, no one deserves to make you feel less.