"I can't right now." -- They can't right now.
"Not enough time, maybe later?" -- They can't right now.
"I'm about to go out." -- They can't right now.
"I have to go somewhere within (x) minutes." -- They can't right now.
What is anyone supposed to feel when someone says "Sorry, not right now"? They can't -- so go do something without them. I feel nothing, to answer the question. I don't understand why you would want to "stomp" anything, which I hope was just an example and not a real intent by you. Just, you know, hang out with some other people if you're in a 'people' kind of mood -- its the way I've always done it. I've never had to end any sort of relationship based on not seeing someone enough: I don't believe people owe me their time, regardless of who they are.