Nearly every professional 'relationship' I've had has been transient after you stop working with them, with people completely failing to reciprocate even after multiple attempts to reach out.
From talking to people I know that this experience is not unique to me, this appears to be the norm, may be it's the industry I work in : software development.
From talking to people I know that this experience is not unique to me, this appears to be the norm, may be it's the industry I work in : software development.