Struggling to Value Friendships

There's something that's become an increasing issue for me over the past few years and I have no idea what to do about it, if anything. I don't know if it's something sociopathic, or related to my ADHD or what, but I just can't value friendships, I can't put enough energy into a friendship to keep it going and I really only have one friend and it's because she actually takes interest in me. I've started identifying as aplatonic, but I don't know if that's valid, if it's just mental illness, or something else. it just seems odd because.. when it comes to a-identities it's always aro or ace, and I feel sort of alone in this issue. I don't think it's sociopathic (and that's not necessarily good or bad, sociopathy is fine in most cases) because I still love people and respect everyone, but it just doesn't feel right. It feels like I'm missing a key part of being human.