When the solid state relay powering this circuit turns on, the 2.2uF will be fully discharged, and the turn on voltage may be an instantaneous (of up to) 90v x 1.414 = 127 volts.
With only 110 ohms in series the instantaneous power dissipation in those resistors might reach a flash 146 watts.
That is rather a lot for a two watt resistor. The explosive release of heat is going to bring about failure fairly rapidly.
Likewise the 2.2uF capacitor may not be too happy receiving current pulses of over an amp. That may fry the foil, unless its a special pulse rated capacitor, which from the size it obviously is not.
These types of circuits are common in some home appliances, and do work, provided the power is only switched on VERY infrequently, and they are usually left running powered up continuously.
If you are pulsing your motor on and off very frequently, its hardly surprising that the components are failing the way they are. Suggest you redesign the whole thing, because there is no simple way to fix it the way it is now.