When you're running game at expert level, and you have a full roster with extra players waiting in the bullpen, one reason to drop a member of your roster is if she drops any one thing you like off the sexual menu or her sexual repertoire. You should have made it clear you like it, and since you did when she did it, and she's done it for you before, she shouldn't have dropped it.
Dropping it means she's either getting comfortable and thinks she has you locked in - meaning she was doing it to reel you in with no intention of continuing to do it, or she's on her way out/favors another guy to the point she doesn't care about doing what you want anymore.
Either way, don't talk with her about it. Don't complain, don't whine, don't demand, don't argue, don't pressure. Don't "negotiate." What's the point? If she wanted to do it, she would have. Desire can't be negotiated.
Don't say anything at all to her. Simply ghost her. If she tries to talk with you after you ghost her, it's because she thought she had you locked in, or the other guy didn't work out. (You should always assume they are seeing other guys; don't indicate you want to be exclusive.)
"Dropping it" would be on a three strikes or less basis. For example, let's say it's fellatio. There can be legitimate reasons she won't want to do it once or twice, like dental work, cold sores, etc. But when it is three times in a row (meaning, over three or more weeks), it means she's dropped it off the menu.
Guys who fall into the trap of thinking they want an "exclusive" relationship tend to end up simply accepting this stuff, because they aren't seeing anyone else and don't want to "start over" with someone else. That is a very common way men end up having a terrible sex life. Early on, she's trying to hook you in. She's auditioning. Don't stick around for it when she stops doing what you like.
One Sign It is Time to Move On
