Dear LIB readers: My marriage is about to crash

From a male LIB reader Please I need your help, I got married in June but before I got married to my now wife, I had a fling with a girl I met in South Africa when I went for a vacation in South Africa, now she called me to say she's pregnant and she's blackmailing me threatening my marriage, I don't know what to do, I don't know if I should tell my wife cause the lady in South Africa said if I don't pay her some amount of money that she's going to tell my wife. Please advise on what to do