This is a very good example how we should listen to the ones with more experience :) But I'm like you. I wold not listen because I would think I can manage everything UNTIL it goes wrong.
I'm happy that your mentor showed you the right direction and that you are seeing it now with different eyes.
I've never had a mentor but I can imagine it can have a huge impact on you (both professionally and privately)
RE: The comfort of having a mentor