tip over the edge(Into a state of emotional instability. I think all the pressures at work and at home have tipped John over the edge. Также используются глаголы "push" и "send". george serebryakov)
warm fuzzy(or warm and fuzzy; OxfordDictionary: used to refer to a sentimentally emotional response or something designed to evoke such a response Olga Fomicheva)