Am I responsible if my new husband did not have health insurance for four months in 2014 before we married in April 2014? I am filing married but separately.

no as you file your return as mfs; however, there are also numerous penalties associated with choosing married filing separately;for example, the overall tax rate will be higher. Anyway, So with all these penalties, there are some reasons to file as mfs;your spouse owes back taxes, child support, or has other liens that would prevent you from receiving a refund; spouse wants to itemize and you don’t or etc. the IRS heavily penalizes those who file separately, but there are still some rare cases where you can benefit monetarily by filing separately. Most couples would do better to settle their differences for one day and file taxes together

Probably the best way is to discuss first things first with your husband, we need to double check the insurance and the benefits you could have.