Some of the bad habits I used to have included smoking and biting my nails. I gave up smoking a couple of years before I had Z. I just stopped cold turkey and I haven't touched a cigarette in over 10 years. I can't quite remember when I stopped biting my nails but it was before I met Husband, so at least 15 years ago.
I guess the one bad habit that I do have is checking my phone. I am quite bad for having a nosy on Facebook whilst the kids are watching TV or after dinner. Sometimes, I'll message someone whilst we are eating. It is really quite bad. I'm making a point of putting my phone elsewhere when we eat now so I don't feel tempted to check it.