So without getting into past topics, I'm engaged in a good power struggle with my current FWB, who also happens to be an ex girlfriend. However, I'm trying to control the frame because as of now, she is mainly in control of when we fuck (IMO not often enough). Here's an example of last night's text conversation.
Me: (7pm) Dtf tonight?
Her: Don't ever use that acronym with me again. And idk.
Me: K. You've got til 9 to decide.
Her: Do we have to have sex? Lol last night was fun (gave her a massage, no sex)
Me: It was, but im horny, and not blowing off my plans for less.
Her: You have plans?
Her: (T+1m) Actually... Hmm. Ok. But I have to be back in my room by 10 and you gotta seduce me lol I'm not horny. So candles, etc. K?
Me: 1030
Her: 1015
Her: (T+4m) K?
Me: I'm in class SPAM
Her: Oh. So 9 ish to 1015. I didn't realize you were in class. Pick me up at my room plz?
Me: K
(40 minutes pass - 8:02)
(FRAME SHIFT - she cancels)
Her: Actually.... I'm sorry but I gotta cancel the plans we just made.

Me: Y
Me: (8:09) Ugh... I so need to find a new fb
Her: (8:15) I think you mean a new fwb
Me: (8:33) No I don't. Only happens when YOU are horny. Fb
Me: (925) A friend would offer to make up/reschedule when they flake. Just sayin.
Her: (943) I am aware. That will prolly happen
Her: (958) I can give you an excuse, though. It's a good one
(...blah blah back and forth... I talk her back into it)
Her (1053) Ah. Well I'm just sitting at D&W's now. If you're willing to pick me up/drop me off, I will give you an hour or so, like we had planned.
Me (1055) I'm not hanging out with D that long (had made plans with him earlier), do the hour after?
Her: Nah, I'm hoping to be in bed. I'm not gonna set an alarm tomorrow n I have class at 10
Nothing happened after this. I could really use some advice on frame control because recently I find the more attractive the target is, the more they behave like this. I think I was doing great until she cancelled. I feel like I lost the frame when I reacted to her, and handled it incorrectly. What could I have done better?
Today we had lunch where D works, but didn't make any plans. Afterwards I sent:
Me: So... sunbathing on the hill after my class gets out at 5?

Her: (after her class got out) Uh idk
How should I respond to this one? I'm leaning towards just freezing out completely until she makes good on a session. Sick of these "idk" responses. For the record, her and I haven't fucked since Saturday morning. I usually make an indirect approach, like the "last night" mentioned in the text was a prior plan we made for me to practice ripping panties off (any advice on this either? I failed miserably) but it never led to sex. Not for lack of trying, either. That's why last night I made my proposal very direct, and in that part I think I did well... until she regained the frame.