I believe that both love and friendship is about trust
Friendship is how much you trust someone with your own private information and how much you believe they have your back, a friend is a person you will be vulnerable around.
Love is how much you will change your life selflessly for someone else because you WANT to (not because they demand it). When you love someone completely, i believe you would sacrifice willingly for their happiness without being asked or told, only because you place their needs above your own. The love for a child is as pure as it gets I believe, you would sacrifice all and anything for your child, even your life. The love I have for my wife of 20 years is truly unconditional and also like that, I would give almost anything for happiness. We have other people in our lives we love at different levels. Some I would take a day and help them move in spite of that feeling like torture. Some I would leave my job and start a company with. Our trinogamous partner I would sacrifice home, money, my own needs, for her happiness as well having her move in with us was a huge leap of faith in the relationship with her, I think that's love. Leaps of faith, leaps of vulnerability, the willingness to make leaps of honesty and trust in someone.