Love comes in many forms.

The love of parents is said to be unconditional. It doesn't involve any possessiveness and there are no expectations in return. Since, they see you as an extension of themselves so it's kind of the way one loves themselves, but only better by making attempts to make up for the shortcomings they faced in their own life. However, not all parents love unconditionally and in rare instances, bad parenting also occurs. Most probably because they didn't have their kids entirely by their own free will and were coerced one way or other either by partner, parents, family, or society.

The love between lovers, if platonic is not about the bodies that touch but souls that dance together. The other person appears the most beautiful person in world even if that's not true objectively. This also involves certain level of possessiveness and lovers are quite sensitive towards the other.

These conditions are trimmed down between lovers that involve a relationship of lust.

The love between friendship is basically trimmed down love of parents and lovers, but it isn't entirely unconditional. While a friend may go lengths at times doing selfless acts, there is a limit to the selflessness. You have to contribute from your side otherwise the friendship withers away.