(Spoilers for GotG 2)
Very satisfying fact (because karma):
Ego, in his madness to reach his goal, killed his own children, probably killed the women he had those children with, and for sure killed the only woman he had every claimed to love because the feeling would make him weak. On top of that, he was ready to kill the child he had with that beloved woman without any hesitation.
Ego believed love and compassion to be weakness and distraction.
But in the end was it love and compassion, the thought of his friends and family, the memory of his mother, and the call his foster-father made (“I don’t use my head, I use my heart”) that enabled Peter to beat Ego, else he wouldn’t have the ability to control his powers.
Not to mention that it was love, care and friendship (no matter how tough that love sometimes may have been) that kept Peter alive all this years.
Peter set his bet on love, and he won.
Ego was destroyed by the one thing he tried to deny and never really understood.