You have a right to your own happiness. Further, nobody else isand only you, are responsible for ityour own happiness.
If you don't leave, you'll be miserable for 2 years. A poor postdoc now might also damage your future career, although probably not fatally. Are you OK with that? If so, by all means stay; otherwise, nobody is going to intervene to improve the equipment in the lab, make your supervisor less abusive, make you happy, etc.
In the end it's your decision to make, but I would strongly incline towards leaving.