When Aunt is dead, her terrified hands will lieStill ringed with ordeals she was mastered by. (9-10)
The speaker imagines that, even in death, Aunt J will be controlled (and terrified) by her marriage, by the "ordeals" that "mastered" her life. Aunt Jennifer is in a passive position here, as if she's being manipulated by her husband even in her death. Sheesh. Can an aunt catch a break?
The tigers in the panel that she madeWill go on prancing, proud and unafraid. (11-12)
Now that's better! These final lines provide an alternate, happier outlook on Aunt Jennifer's future. Even in death, she may be constrained by her husband, but her tigers can prance on "proud and unafraid." Aunt J thus is able to construct a different, imagined life for herself in art. Art is where she, as a woman, can exert control.