Why according to Mirabell do the people of the 17th century commit disagreeable and dangerous actions?

From the Text:

Why do we daily commit disagreeable and dangerous actions? To save that idol, reputation. If the familiarities of our loves had produced that consequence of which you were apprehensive, where could you have fixed a father's name with credit but on a husband? I knew Fainall to be a man lavish of his morals, an interested and professing friend, a false and a designing lover, yet one whose wit and outward fair behaviour have gained a reputation with the town, enough to make that woman stand excused who has suffered herself to be won by his addresses. A better man ought not to have been sacrificed to the occasion; a worse had not answered to the purpose. When you are weary of him you know your remedy.