Sense of joy / gratitude has dulled even though my circumstances haven’t changed.

In the last few months I’ve found that I’m not as easily stoked or excited about things in my life that are awesome. I do a gratitude list every day and even on the worst days, I could easy get excited about the simple things like my home, my health, or nature. But lately when I try to focus on those things, the joy is dulled. I think “ya so what?” I don’t understand because they haven’t changed which means something in me has changed. I don’t know why or what. I don’t like this because intellectually I know that I I should be overjoyed with all the good in my life but I can’t seem to get myself there anymore. I don’t want to be someone who takes things for granted or can’t enjoy the abundance that’s already here. I tried a model and the prevalent Thought is “ya so what?” when I think of the Circumstance (i.e. my home, my neighbourhood, my health). I want to be more thankful and full of gratitude but it’s just not there.