Unfortunately no. Any gain from the sale of stock is taxable income. There are no exceptions for a person in your circumstances. You may, however, take a deduction for your health insurance expenses as part of you medical deductions on Schedule A if you itemize your deductions. Deductible medical expenses are those that exceed 7.5% of your adjusted gross income in 2018.
[Edited 03.25.2019 | 3:39 pm pst]
