When one friend befriends another through your introduction, soon putting more effort into that person than you do, simultaneously making you seem
less desirable and devaluing both your
original friendships. This can happen consciously or unconsciously. Notably, one does not tend to ever
make any new friends for themselves through the friend poacher.
I used to be close with Guy until I introduced him to
Buddy, who started inviting him out all the
time; I think
Buddy is friend poaching, especially considering I've never met any good friends through him.