There are three conditions that need to be met no matter if my love is to be given to a friend, lover, or even family member. And if these aren't there then my love won't bloom, grow, or will die very quickly.
Trust: I don't need to know everyone's business or even my significant other's every thought, I simply need to know if I ask them a question that affects me directly they will answer honestly. Even if the answer is not to my liking or that it's something they're not willing to answer. I need both to to trust that someone has my back, and they say to my face whatever they say behind my back. Which leads to...
Communication: I'm done with any relationships where communication is a guessing game. As I got older I thought that adulthood meant that when a problem popped up the folks involved would sit down and resolve it like "grown ups". Turns out if someone avoided issues in their 20 and 30's they're not going to find themselves magically in their 40's cleaning up their messes and working things out. More likely they'll just leaves bigger messes in their wake. And to that I say: no thanks!
Love is not enough to get us through when we are not safe, trusting, and communicating with the people we proclaim to care so deeply about. It's just not. Because to truly love someone else we need to value ourselves enough to ensure our relationships are healthy.
And trust me, I love myself unconditionally enough to love conditionally ;)