The marriage would still be valid.
Whether or not you can claim a fault divorce depends on the state you live in.
A fault divorce may be granted when the proper grounds are present and at least one spouse asks that the divorce be granted on the grounds of fault. Not all states allow fault divorces.
The traditional fault grounds are:
* cruelty (inflicting unnecessary emotional or physical pain) -- this is the most frequently used ground for divorce
* adultery
* desertion for a specified length of time
* confinement in prison for a set number of years, and
* physical inability to engage in sexual intercourse, if it was not disclosed before marriage.
Since his inability was disclosed before the marriage, that would make the grounds invalid.
In some states, a spouse who proves the other's fault may receive a greater share of the marital property or more alimony.
More on divorce