People typically operate under the assumption that some of their relationships are time-tested and therefore, tough enough to withstand any pressure.
No relationship is tough enough because human beings are mostly fragile on the inside, and if you apply the right pressure, most of them break.
Relationships, whether business, filial or romantic, suffer the milieu of ending with the abruptness with which they started. My advice, treat your relationships with customers, business partners, colleagues, siblings, parents and of course, lovers as you would mini roses. No relationship is ever too big to fail, so water them every day.