-- Like I said, the decision about this really only applies in swing states due to the Electoral College system.
If you live in a solidly red or blue state, you can sit out the Presidential election or vote for a 3rd party candidate without having to worry too much about the ethics of your decision.
However, if you live in a swing state, a decision to not support the Democratic Party nominee (Clinton or Sanders) would take away my adult daughter's ACA health care coverage. She's a part-time college student with a part-time job. The ACA is providing her with low-cost insurance. Repealing it would hurt my child and that will happen if the GOP regains the White House.
And, if you live in a swing state, a decision to not support the Democratic Party nominee (Clinton or Sanders) would take away the ACA Medicaid expansion from working poor who don't qualify for the ACA subsidized marketplace insurance.
In Louisiana, we just elected a Democratic governor who is accepting the ACA Medicaid expansion that former Gov. Jindal rejected. In a few months, we will have over 400,000 people getting health care coverage and this coverage will go away if the GOP regains the White House.
In an ideal world, we would have a European-style single-payer health care system. But we don't live in that world. We have a Congress that wouldn't support single payer health care and it will take a massive shift in congressional representatives to get there.
So you need to ask if your distaste over Hillary Clinton is more important than the thousands of people who will die due to lack of health care coverage if the GOP wins and the ACA is repealed. Speaking as a father, I'm more concerned about my daughter's well-being than political purity.