If you love or care for someone you automatically expect something in return. Unconditional love is difficult to give.
That is a thought to ponder. It is possible though to love someone and not to expect something in return. You might hope that they will be happy, but you do not expect it.
I think the kind of love you are speaking of is the kind of love shared in a "sexual" relationship. This kind of love is really more of adoration, attention, and as Don Miguel Ruiz defines it, "control and manipulation".
Unconditional love is extremely difficult to grasp because we have been conditioned to believe that love is so many other things that it is not. Unconditional love exists when you simply want the best for someone, even if that means you are to be removed from their life. It is the love that you have for someone even if it means wishing them well in death. It is a freedom of sorts.
Unconditional love is accepting others in all of their glory, understanding that their path is not your path and you have simply been blessed enough to share in a small part of that.
Unconditional starts within. First, you love yourself unconditionally and then you are able to see everyone else without judgement.
I have only experienced this in fleeting moments and small time framed-doses. These days, I work really hard at it. When it is in alignment, it is amazing.
Practice, practice, practice. I pray that within this year I master it.