Is Picking up Bad Habits

Editing for yourself is hard work because there are times you see mistakes but the wording is so wonderful you try to find a fix. We're all guilty of that. Finally, when one realizes it can't be fixed the mistake is erased and all of our wonderfully crafted words along with it.
Editing for others is much easier, not because you're being vicious, but because pointing out mistakes is a teaching process. So you slash although a tinge of guilt grips you. Then you remind yourself it's for their own good. They'll be better off for it. You fix their dialogue, their narrative. Many times, however, you don't pull out soon enough to prevent their mistakes from corrupting you with the ferocity of an Asian virus.
When you get back to your own manuscript, to your horror you find lines of dialogue written by you that resembles something from the 40's when lines like, "Gee, you're a great guy, Joe," were standard. Your dialogue has become archaic, clumsy, corny. Not to mention what I've done with the narrative. Wordy line after wordy line of description that's not needed. What to do?
Do I just ignore it as writers and produces did in the opening lines of The Pacifier with Vin Diesel--who I think is a hunk? He gave a short, corny speech on the fact that he and his men were Seals. It confused hell out of me because this was a recent picture, not something out of the 40's.
Now, Before everyone writes and tells me about the classics from that era, I'm aware of them and I still watch them when they're on TV. But the dialogue is from that era. It doesn't fit now.
So here I am with lines like, "We're cops. This is our job," in my manuscript. Ouch. That hurts. I need to do a Law and Order marathon to get it back because I'm slipping into the past.