My wife told me the other day that she doesn't believe in the afterlife?

Sounds like your wife has some sense.

Don't waste your one single existence on your mythology.

Not much. Just support her in her right to have her own belief and tell her that you'll have to agree to disagree. That will probably make her more likely to question her belief and wonder if there is an afterlife.

She probably already knows that the afterlife is as real as Jesus.

I think you're right, considering I'm not convinced Jesus was real either....

If you tell her that Jesus (as a divine entity) isn;t real either, then she will agree that the two are equally (un)real.

You mean eternal life? You can't convince people. You can tell them what the Bible says and pray for them, though. It's a personal choice, though to believe or not to believe.

Did you manage to convince her that Jesus was real?

Start by proving Jesus was real.

Take her to church! Read her the bible! Tell her the stories of saints.

Nothing, because she's right.