Should I quit?

i met my current boyfriend in a funny way and been in a relationship for 1& 1/2 yrs. we both worked and still work in the petroleum industry but different companies. we used to talk everyday discussing business for 2months without physically meeting and would tell me how much he believes iam the right woman he wanted and how he wanted to be my man. i accepted to meet him for the 1st time and made him wait for me for an hr at the resturant. he was so happy to see me and we started dating. he isnt an attractive man but i love him, his way of life and fall for him to the last nerve of my body. recently found out that he has been having an afair with a casheir at my workplace even before meeting me. i told him i was leaving him if he doesnt end it and choose whom he wants. he has changed to a better,romantic,sweet and caring man and communication is soo good clear and now he keeps reminding me how he wants to meet my family. but he still flirts and communicates to the other lady and i dont know what to do. we dont live together but we speak all night each night. kindly advise me before i go crazy.

If he just communicates with her then that's not a huge problem, he choose you! & he's ready to take the next step. I would go for it!