How do I monitor Pi-hole with monit?

@Sjonnie: thx for your quick answer and solution. Happy with it!

I'm a beginner with Raspbian, so I'm not sure if I can help you very much.
I have one addition to the script to monitor Domoticz. From the Domoticz wiki I pasted these lines. These lines work perfect for me...

check process domoticz with pidfile /var/run/domoticz.pid
start program = "/etc/init.d/domoticz.sh start"
stop program = "/etc/init.d/domoticz.sh stop"
if failed
url http://127.0.0.1:8080/json.htm?type=command&param=getversion
and content = '"status" : "OK"'
for 2 cycles
then restart
if 5 restarts within 5 cycles then exec "/sbin/reboot"

Is it possible to add something like that to the lines regarding Pi-hole? Whats your opinion on this?

Thx/Bedankt!