One thing I do a lot in hard situations, which may sound really dumb but it does help me, is that I imagine I’m filming a documentary on how to handle that situation. In my head, I run through all the steps, I have a “narrator voice” explaining what’s happening. It’s weird, but it keeps me on track. For instance:

Narrator In My Head: The first step is to explicitly make sure the person you’re addressing is ready to engage in the conversation.

Me In Real Life: Honey, there’s something I’ve been meaning to talk to you about, but I worry that it’s going to be hard to hear and might upset you. Is now a good time?

NIMH: If the other party agrees, it’s time to gently but truthfully say what’s on your mind.

MIRL: Ever since November I’ve noticed that your natural scent seems different. I know you shower every day and wear clean clothes, so that makes me think it might be a medical problem..

NIMH: Now give the other party time to reflect and process what you’ve said. Wait for them to make the next move.

I don’t know, making it a “documentary” makes it kind of less personal so I’m not as nervous. Your mileage may vary.