I don't know what the power structure and equity structure is in the organization, so I don't know how vulnerable your job and your ownership in your company is. But in general boards can't simply fire people without cause. I would strongly suggest that you start by documenting absolutely everything. Make sure all meetings are minuted and keep your own copies of those minutes. If the bad board member says something to you outside a meeting that has some bearing on your relationship or the company, find an excuse to get him to email it to you. You can even record phone calls in many states with only one party privy to the fact the call is being recorded. (IIRC California is not one of these states).
Secondly, get chatting to a great corporate attorney. Email me if you need a Seattle reference. You need to get a deep understanding of how vulnerable you are and what levers you have to protect yourself and your business. Then (and I say this again) keep records of everything in the context of knowing what will help your situation.
This quote suggests that you are kicking ass at your business:
"We went through the status of the company, and at least from the outside it sounded good. In fact it sounded great: three major versions of the product shipped, multiple iterations and a few pivots under their belt, revenue was growing even faster than plan."
The key here is "...even faster than plan.". You and the board agreed to a plan and you over-delivered. It's important that you document your own performance - get hard evidence of the success story above.
Other than that, keep doing the great job that you clearly are doing and save the war chest you're accumulating for the crunch if it ever comes.