Let's explore options to see what might help. Smart phones and speakers recognize your voice and can display a text transcription of it. So it's like writing a note and showing it to the hearing impaired person. Of course when all else fails you can text each other over your smart phones with the ring vibration mode turned on.
How about a little sign language? Everybody already understands some simple signs. That reinforces other habits that help like remembering to turn and face your husband when you speak to him and to reduce all the noise sources in the environment (like loud TVs) that make it harder to hear someone. I find myself automatically yelling to my wife "I CAN'T HEAR YOU!" which of course exasperates her to no end. How can I break the habit? I must take the time to physically face her (with a smile on my face) and calmly ask her to repeat what she said without yelling at her.