You shouldn't get mad if somebody says NO to you.
I know that after "NO" you think there must be something wrong with you or your proposal - not handsome, smart, funny, tall enough and other things, and then you turn that ickiness against the person who rejected you.
You'll start to judge them, you may even start to hate them, and then resent them for spoiling something that could have been great for you (or both). Your harboring of those nasty feelings, judgments, and resentments - is only gonna screw YOU.
If that is not a good reason for not getting mad at someone for telling you NO - which means just NO (or: I don't want to) by the way - not that: your destiny is sealed, there's an idea for you to consider:
Try to apologize.
Part of my healing involved a call to my ex one day out of the blue, apologizing for putting him in a box. For judging him, not only for what he has done, but also "Who does he think he is" for not taking me back?
I was the judge of his momentary preferences. Whether it was exchanging me for a moment, or leaving me for good. His reasons are his reasons.
I was righteous in my own wrongdoings and stubborn stances, and when the rejection came, of course I turned the ickiness it had stirred up within me against him. The ickiness was mine! if I think I am unlovable - I have a problem. Not him.
Therefore, try and apologize for blaming your 'rejector' for whatever their NOs had stirred up within you, so you then began harboring resentments because the ickiness just wouldn't let go. You were blaming and judging before knowing what was going on with the person in question.
NO means "it won't be happening".
So, you might as well sort yourself out, and leave the rejector out of it?
Your apology will go a long way. NO is really not the end of the world. Your attitude is everything. Do not worry about being rejected. Just go and find your YES.