yeah, i feel ashamed when i ask for something and the answer is 'no' too. you know how there are lists of cognitive distortions that should be challenged? (ugh). well... here are a couple around this issue:

'if someone says 'no' then that means i shouldn't have asked'
'if someone says 'no' to a specific request that means they are rejecting me'

those are a couple that i remember anyway. of course, i don't think trying to challenge them / beat oneself up over them works to alleviate them. but it is worth thinking that they aren't true even if they FEEL true. just to be aware of it... so that one can attempt to act in spite of the feeling. and so that one can attempt to soothe the bad feeling with the reminder that it was okay to ask and that the person can still care very much even though they said 'no' and it was okay that they said 'no'... all at the same time.

that being said... its so hard that mostly i avoid asking...