can leave you sometimes angry even though you might not know why.
here's a tip: stop and examine your expectations (cause they are going to need some change).
if you and your friend are drifting apart, those habits are no longer normal and expecting them is only going to bring you constant disappointment.
to save yourself pain, you must change your expectations for how close your friendship is and how you expect your friend to treat your relationship.
then, you may have to live with this "new normal," these new expectations, for a season.
because we live in a cause and effect world, this person's change has affected you. you are responding in some way. 