Do you feel guilty when you kill insects?

I have a belief where insects are concerned. If they are outside, then live and let live. However, if they are in my home its another story. I can't have an infestation in my house, especially ants, which can be very annoying to have around. So, do I feel guilty taking care of them, no because if they had stayed out of my house, I wouldn't have harm them. There is only one form of insect life that we have allowed to live in our home because they don't cause any trouble, and that is a lizard that has lived in our kitchen. This type of insect or reptile whatever you want to call it, if a good thing to have around, because they eat other insects. So we co-exist with this lizard.