Yes, your load is putting big spikes on your power supply and you don't have any capacitors to stop them getting to the mcu. You also need flyback diodes on both coils or you will shorten the life of various components.
Edit, electrolytics alone will not do, you need the small ceramics as well.
oh i forgot to mention, when i added a load, and the load is powered, the system is become ok, the main problem is when the switching is done,
for example,
i activated the relay, the system restart, and become ok again,,
i also forgot to mention that the relay config is normally closed, the load is active even the relay is not activated, and if i activate the relay, the load will deactivated,
Have you included the flyback diode at the Relay coil and the Magnet?
The ceramic capacitators of 100...220nF have to be included at the 7805 at the input to GND and the Output to GND as near as possible at the Pins of the Voltage Regulator.
Additional a 100nF ceramic capacitator should be included at every IC as near as possible at the supply pins.
When a coil was switched off the magnetic field inducts power to the electrical connections.
Because the circuit is open this voltage can achieve very high values in that no current was drawn.
The Flyback Diode draw current out of the coil an so the induction voltage is quite low.