Insiders say Michael Bolton’s three adult daughters were the reason for his split from Nicollette Sheridan. “Isa, Holly and Taryn disliked her,” one close source explains. “Michael played referee and tried to smooth things over but when push came to shove, he chose his daughters over his fiancee.” After an on-off relationship that ended in 1997, Michael and Nic reunited in 2005. They announced their plans to wed in 2006 but split last month. “Nicollette is shocked and heartbroken,” our insider tells us. “But Michael told her absolutely nothing will come between him and his daughters.”