> as long as the counterparty actually accepts the invitation every so often

Per the article, the collegiate counterparty did accept other invitations:

  We ended up hanging out quite a bit during those early months.

The social ritual in the article's title was specifically about party invitations:

  “Why do you keep inviting Anna out when she’ll just say no?”

  “I know she’s always going to say no, but that’s not the point. I invite her out so she’ll always feel included in the group.”