Yep, it sucks that one little comment can throw you off kelter. It happens to me sometimes and happened just a couple days ago. H made a comment about something and I just felt tears come to my eyes. I was sitting next to him so I had no choice but to blink them away in a hurry then get a little cry when I was by myself later. But whereas before I woud have been down for an entire day, I was only down for about an hour so I can tell you that it does get better with time.
Holidays, birthdays, anniversaries. These are all difficult because your plans would usually include both of you as a couple. It is tough and nothing anyone can say will make it easier. If he is making plans that don't include you, you make some great ones that don't include him. Easier said than done but what choice do we have? At first it is about surviving this but eventually it will get better. Eventually....