good sex, but crappy relationship.
it is but isn't....too much a like you would clash, such as I and my husband, we are very much a like, and yes have ti agree he is the male version of me and vice versa. I have to usually step down if we clash so it does not get out of hand, but we do find a balance that works, because we both know we are very similar to one another, it is good and bad, at times,
That adage, re-quoted by FallingStarr, describes my wife or 32 years and I. I am outgoing, she is quiet. I am a hellraiser (or was when younger), she was meek. I can talk to any stranger and carry on a conversation, she will give one word answers to strangers or say nothing at all. Switch us around, and we'd still be the same couple.
Most people like people who are like them Throw in some interesting differences, and there it is!