Would it be weird to quick add a girl on Snapchat if I’ve not seen her for a year?

She keeps appearing in my quick add section and I don’t know if it would be weird to add her. We were in the same class in high school (we’ve both since graduated). We didn’t chat that much, but when she did she was really friendly to me. The issue is, I have autism so I don’t know if she was being friendly out of pity or because she actually wanted to chat to me, I don’t know if I should just add her
Would it be weird to quick add a girl on Snapchat if I’ve not seen her for a year?
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