Did McCain kick his first wife to the curb and cheated on her because he didn't like her fat and crippled?

When McCain married his first wife she was a gorgeous model. His wife waited for him while he was a POW in Vietnam. After a car accident she was crippled and gained weight. When McCain returned from Vietnam, he cheated on her and later divorced her, which he openly admits for reasons unknown. What happened to 'til death do us part' and 'for better or for worse'? He married his current skinny wife and she makes it a point to stay thin. He selects Palin another former beauty queen to be his running mate. There seems to be a trend.