How do I cope with doing three jobs for one shaky paycheck?

Your industry is shrinking, and instead of shrinking your workload, they piled the empty jobs onto you. Now you do the work of three people for one paycheck that never feels secure. That is exhausting and unfair, and pretending it's fine will only wear you out faster. Name it plainly: you are being asked to carry too much. You cannot do three jobs well forever, so stop trying to. Decide what actually matters most and let the rest be merely good enough. You will not win by burning yourself out to hold a role that keeps expanding no matter how fast you run. Protect your energy like the limited thing it is, because the job will take all of it if you let it. At the same time, look up from the treadmill. An unstable industry is telling you something, and it is wise to build a small margin of safety, savings, skills, options, before you are forced to. You are not disloyal for protecting yourself. You are being sensible. Do the work you can, well, and quietly prepare for whatever comes next.