I've struggled with this question A LOT myself. Based on what you said I think I'm a lot more antisocial than you, but I think we've had pretty similar experiences overall.
For a long time I thought I was gay, actually, because I didn't like girls (romantically or sexually), but over the last half-decade I came to realize I don't really like anyone in that way. For now, I just identify as vaguely queer but I do believe aro/ace fits me rather well.
I guess my point is that, even if you're "just" antisocial, at the end of the day you don't feel the want for a romantic or sexual relationship. That makes you aro/ace. I don't see the point in labelling yourself that precisely anyways, personally, just live your life and that should be enough.
You shouldn't feel bad for being the way you are, and there'll always be people that you can relate to. Consider seeing a therapist and talking about this though, might be beneficial if it's getting you down.
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