Diane is strangely unnerved as she finally hears what she's been waiting for from Mack. Aware that he is implying a deepening of their relationship, she tentatively reminds him they’ve always been casual before. The couple have a heart to heart and he finds it hard to open up, but she teases out his true feelings. He admits he wants to stay around for the long term, stressing it is because of her. He admits he's never settled in one place, been committed to a relationship or faithful to one woman before but wants to change for Diane. Diane is overwhelmed but uneasy at Mack's declaration. (thetvdb.com)