Why in mostly cases wife's don't like mother in law and mother in law don't like daughter in law, very rare have love from heart ♥?

Why in mostly cases wife's don't like mother in law and mother in law don't like daughter in law, very rare have love from heart ♥?
Why in mostly cases wifes dont like mother in law and mother in law dont like daughter in law, very rare have love from heart ♥?
Why in mostly cases wife's don't like mother in law and mother in law don't like daughter in law, very rare have love from heart ♥?
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