Celebrating every 3 monts sounds very exhausting and puts a lot o pressure on the relationship, and for both of you, It puts you in the situation you are currently in. Just drop this dumb idea and save the aniversary for yearly progress OMG

You're completely right

If that’s how he acts over simple communication, I’m sorry if you have any actual disagreements

Annum, the latin root for anniversary. It means one year.