I think most ppl are fine with it if it is only once and you seem genuinely sad about it. I am fine with ppl forgetting we even met I am even playing along pretending it is the first time we meet, so far has it only been ppl I met maybe twice in my life(except one person). I have only met one person who actually got sad when I forgot her name. She asked if I was not as happy as she was to see me… That hurt, I remembered her tho! But not her name.
I think it is worse when I have to introduce myself everytime we meet and it has been over 3 times… One dude he never remembered me until the 5th time then he said "heey we have met before right?! " he even looked genuinely happy and I felt “finally we can stop pretending” but then the next time we met he introduced him self again… I remember you Felix!
Funny to see this question here a few weeks ago did I see someone link this https://m.youtube.com/watch?v=Nqxjfp4Gi0k&feature=youtu.be
The video shows how to create a salt based pcm (phase change material). You can also buy packs like these but I thought it seemed more fun to create it myself, so it will be my summer project when the heat is not barrable. I think Putting it under a cap would do wonders.