It depends. However, Maryland under no circumstance can tax your military income because you are not a Maryland resident. Maryland can and does, however, factor in your income to determine how much tax is on your husband's income.
What Maryland does is to calculate what your tax would be on all of the income, and then prorate the tax based on the percentage of income actually earned in Maryland. But your income is not taxed there.
Essentially the calculation that Maryland is making amounts to taxes of ~50% of my husband's income
There is another possiblity, which is for your husband to file separately in Maryland. This guarantees that your income is excluded. Before you try this, however, you may want to double-check that your state of residency is marked as Florida and your W-2 is marked as active duty. Then, if you wish to see if filing separately on the MD return will be better, see this FAQ: <a rel="nofollow" target="_blank" href="https://ttlc.intuit.com/replies/3301995">https://ttlc.intuit.com/replies/3301995</a>