FETs or NPN transistors open at 0V at base in CircuitLab or is something wrong with my circuit?
The symbol you have for J2 is a JFET, not a MOSFET. They are depletion mode devices that would show the behavior you are seeing as they need a negative voltage on the gate to turn them off.

Also, measuring the voltage at the junction of a FET source and a diode can possibly be an issue because if both devices are turned off after being on, the voltage can be maintained at the node by capacitance. You can put a high-value resistor to ground to avoid the problem.