Sorry you are getting blindsided by the unexpected. You do need to clean up the incisiveness of your communication, not because your communication is particularly unclear, but because NRE is fogging up his vision and making him see everything in a blur. To get what you need and want, you have to be extra assertive.
Re (from reflections):
Ah, but a plan is not a promise. A plan is like a trip itinerary; people generally see it as something that can be adjusted depending on unforeseen circumstances. Perhaps calling it a "plan" was a bit of sophistry on his part, but I still advise extracting an explicit promise (about whatever it is) from him in the future. If he doesn't explicitly promise, then prepare yourself for the possibility that he might end up changing "the plan."
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The only way to be sure of that is to flat out tell him: "If you act on a gray area, it will be very hurtful for me."
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I would consider telling him, "I need to know exactly what I should expect before it happens."
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But does he see that? NRE has a way of putting blinders on.
It would be disingenuous for me to imply that you weren't doing your part. You are doing your part. It's just that when you're dealing with NRE, you have to go the extra mile in order to be heard. His head seems to be floating in a rainbow-colored cloud, where everything's going great and everyone's taking everything in their stride. You have to be the meanie here and pop his bubble.
Re (from reflections):
"I offhandly asked him if he had used protection with her, with the expectation that he would reassure me he had. He told me he hadn't. We had talked about that before his date, with me frequently saying that I would feel more comfortable if he did, at least for the first time, at least while I'm still trying to get through all this. He told me that he planned to."
Ah, but a plan is not a promise. A plan is like a trip itinerary; people generally see it as something that can be adjusted depending on unforeseen circumstances. Perhaps calling it a "plan" was a bit of sophistry on his part, but I still advise extracting an explicit promise (about whatever it is) from him in the future. If he doesn't explicitly promise, then prepare yourself for the possibility that he might end up changing "the plan."
Re:
"I felt like after that discussion, he would recognize how hurtful acting on gray areas were for me."
The only way to be sure of that is to flat out tell him: "If you act on a gray area, it will be very hurtful for me."
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"I think I can process all I want beforehand, but things that I didn't expect would be hard are harder after they happen."
I would consider telling him, "I need to know exactly what I should expect before it happens."
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"I'm trying to own up to my responsibility for not being clearer in my communication, but part of me feels hurt that he isn't extra sensitive to my concerns, given that he sees how hard this is for me to process."
But does he see that? NRE has a way of putting blinders on.
It would be disingenuous for me to imply that you weren't doing your part. You are doing your part. It's just that when you're dealing with NRE, you have to go the extra mile in order to be heard. His head seems to be floating in a rainbow-colored cloud, where everything's going great and everyone's taking everything in their stride. You have to be the meanie here and pop his bubble.