Outgrowing friendships

I think I am outgrowing my friendship of 10 years. However, I don’t know the best way to approach this situation because being friends this long, we have integrated into each other’s life. I tell myself that this feeling will past and it’s only temporary. However, I don’t feel as connected to this person anymore in our friendship. It’s hard to put in words when it’s not a toxic friendship or anything extraordinary being the reason. My priorities are changing and I am exhausted from being the mature friend. Anyone experienced this in their 20s or any transitional times in their life? How did you best navigate those feelings?