Friendship changes when one person becomes responsible for maintaining all of it.

When all the planning, reaching out, and remembering falls to one person, the relationship has quietly become something else. It can persist that way for years, held up by the one who keeps making the effort, and warmth from the other side is not the same as participation. The imbalance usually becomes visible only when the maintaining person stops.

If you suspect this, you do not have to make an announcement. Simply stop initiating for a while and see what happens. Whatever the result, you will have accurate information about what you are in.