6 rounds of interviews, extreme lack of communication, after hearing nothing for months I assumed someone else got the job, only to be informed that they weren't going to fill the position

I was contacted by a recruiter for this position. Many of the questions began with "Tell me a time when...:" I felt as the HR person sized me up right away, and she was not particularly friendly. It took them more than a month to get back to me to let me know I wasn't going any further in the interview process. The only feedback they gave the recruiter was that "there were stronger candidates," but no other information - what aspect of my personality or experience wasn't "strong" enough? That type of feedback isn't helpful to a job candidate.