Take it personally
You made something great, you broke through the roadblocks and finished what was thought impossible. You showed it at the staff meeting and it flopped. Turns out you were solving the wrong problem, and not only that, you solved it the wrong way. Full on blew it. What should we do in this situation? Take it personally. Sulk a little bit. They just told you your baby is ugly, not only ugly but smelly and probably is never going to grow into those ears. Jerks, all of them.
Taking criticism personally is the curse of the craftsman. You put a piece of yourself into everything you create. Those emotional twinges are not inappropriate.
Be careful though. There are real opportunities for failure here. By identifying too deeply with our creation, we rob ourselves of the opportunity to grow from the experience. An amateur will never get out of the emotional funk brought on by solid spot on criticism. Their next attempt will be at 90% then 80% then eventually they will simply coast along, having lost their willingness to emotionally connect with their creation. It is a defense mechanism. It spares them the pain of seeing their baby stumble.
Conversely, stellar craftmen are able to propose designs with passion, argue deeply for their position, and in the next breath, tear their ideas to shreds. They fully acknowledge every deficiency, knowing that a singular idea does not define them, that their worth is manifest in the process of creation, in the quality of the end product, and not in how many of their proposals were deemed brilliant during the brainstorming meeting.