It is one of those things that can hurt the fragile ego because it points to a feeling of unwantedness and does take some amount of objective introspection to realize for the more needy person. Either one can close one's eyes to it and continue as if this wasn't true or in the extreme, say "I don't need that person too!". Or just accept the fact and say fine, though I need the other person more, I won't feel so bad that that person won't seek my thoughts at the same rate. At least this way, the bond stays and flourishes.
This may point to an inferior quality in the seeker, who needs to fill spaces with the emotional dependence, but we all lack something in us and there is no harm in sincerely seeking to fill the void. But lest we get hurt, we must lower our expectations in hoping for the same emotional satisfaction that we think we are giving the other person when we actively seek that person's time to ourselves. Also, this realisation may help identify other relationships where we may be the so-called anchor for someone else, and perhaps we can help assuage the other person's feeling, for we have now the power of empathy in such situations.
Pretty heavy, no? <insert favourite smiley here>