I think you can get your point across without being a d!ck.
If in a "relationship"-
-Sorry, this isnt working for me so I am going to go a different direction. Take care.
-You know it seems like things have changed and I dont really feel like this is something I want anymore. Take care.
If a plate or someone you are trying to meet up with (new plate) and her actions are hit and miss and you want to stop putting in any effort..... OR she is either attention whoring, etc.
-I am going to politely withdraw that invitation for drinks. Seems as though something has come up. Take care.
-On second thought, I dont think you and I are really all that compatible. Take care.
I really try, no matter what the circumstance, to not burn bridges although I have on a few occasions. The fewer words to get your point across, the better. Never answer their questions as you walk away....just keep stepping.
I smashed a chick last year for 4 months and then she suddenly went cold. I walked away. We remained friends on FB, INSTA, Snapchat, etc.
Randomly she would send me texts like "Its a nice day to be out on your boat today", "hey I was thinking about when we.....blah blah".
On two occasions I offered to meet up in response to her texts. Both times she went silent again. It was just a feeler to see if she could still meet up with me IF SHE wanted. The times she messaged me and I blew her off with no invitation, she came back with something like "why are you acting different to me" or "why are you being MEAN to me all of a sudden?".
The last time she messaged me (2 months ago) she said "hey....I have a question. Did you tell someone that I was a gold digger?"
I said "Of course not. But I told several people that you were an attention wh0re. The few times I bit on your texts and offered to meet up, you just went cold again after you got the validation you were looking for. I never said anything about gold digger, although the thought has crossed my mind. Regardless, my interest in you expired a long time ago. I hope you fall into a pile of money and attention and get everything you want in life

"
Immediately after I blocked her on all Social Media and blocked her number.
Problem solved.