You're suuuuuuper close to it making more sense to file Married Filing Separately. This is usually the best way to reduce taxes when one spouse has large medical bills. In fact the turbo tax article on the subject uses almost the same numbers as your situation to explain it.

Based on the info provided though there's no way we strangers on the internet could tell you which method will work out in your favor though. You need to get yourself a good tax software, I prefer Turbo Tax but I know many will hate on it. Run the numbers both ways for married filing jointly and married filing separately to see which method reduces your tax bill the most.