I want to apologize in advance, I am 32 and I remember this feeling but I have hit an age where it doesn't happen as often. Can it really be called love if they aren't involved? Love is something people DO. It requires interaction. The people I pines for in my teens and early twenties I don't talk to any of them now and in some cases their lives took dangerous paths I am so glad I was never a part of. Very very few people are with the person they dated in high school, so if you can't reassure yourself knowing that it is usually for the best to not be with someone who doesn't care for you the same way try to take solace that maybe you will meet at a reunion and things will click then. I have an ex from when I was 18 who I adored but things never panned out. If I was ever single again at this age though I might seek him out because despite his flaws he was a kind person. We don't get to pick the timing sometimes.