smarts > pains
4 Of them, that to him buxom are and prone:
buxom > yielding prone > ready [in mind], eager; given, inclined
5 So thought this maid (as maidens use to do)
thought > considered (esp. in connexion with marriage) use > are accustomed
6 Whom Fortune for her husband would allot,
Whom > [He whom]
7 Not that she lusted after anyone; 8 For she was pure from blame of sinful blot,
blame > fault; charge, accusation
9 Yet wist her life at last must link in that same knot.