>> reporter: mary robertson was diana spender's boss and friend when she was dating prince charles in 1980. >> i think there was a great deal of pressure from his mother and father to get married and produce some heirs for the throne. i think diana was just sort of the right girl at the right time and the right place. >> reporter: insiders say charles did care deeply for diana but was pressured to marry before he was ready. no surprise that their son william would not be pressured to propose. one spring day, kate was at work, an accessories buyer for this clothing company. >> she gets the call on the cell phone, the other employees can hear what's going on in there. it's not pretty. she's hearing the news he's breaking up. she doesn't want this to happen, an emotional conversation going on. the big breakup call. >> reporter: "the sun" newspaper