Friends - they have a reason to benefit from you. If you smoke weed, they smoke weed with you, if alcohol it's alco. If you are above them in success, they befriend you to get to where you are. Your pal in gym, needs someone to progress with for his own benefit aka better motivation in group(and maybe to spot him lulz). That friend that goes out with you, needs you for a wing man, or to treat his social anxiety.. If you have kids, they will befriend you for the sake of their kid to have someone to play with. If they are lonely they will befriend you to not feel lonely, and use you for their loneliness. They don't really love you, they just love what they can gain from you.

Parents - they just want to raise you because you are their genes, and they want you to biologically continue their genes (the amount of time your mom says to you to get a child).. They want to extend "themselves" after they die.

Isn't relationship with woman the same? She is just your friend that you fuck because we are naturally wired to reproduce. Isn't the idea of love easier to reject from this point of view?

No one loves anyone.