Arts in the Barn, at 17 Hathorne Point Road in Cushing, is hosting the exhibit "3 Women in the Abstract" with Wendy Clayton, Erika Manning and Marli Thibodeau.   They are abstract painters and do large canvases depicting movement and themes that are dreamlike or relate to past impressions of their lives.    Opening Celebration: Friday, July 15, 5 to 8 p.m. Hours on Saturday and Sunday, July 16 and 17: 10 a.m. to 5 p.m.   artsinthebarncushing.org