We are a "secret". am i wrong?

You can never be happy if there will be the two of you in his life. Is he married with the other woman? if yes, then time for you to go away because the relationship you had with him is such a big mistake from the start. However, if he is not married you need to talk to him about the other woman, let him decide whom between the two of you he will choose. I know it will be difficult and might as well be hurting on your part to do that but might as well be the best way for you to be happy and have a good life later on. My girl, you can't be happy as long as your boyfriend has another woman, it will only result to quarrel the moment she will know. you will just compete with her and you can't never have peace of mind. Better let him decide now whom he will choose between the two of you, it would be the best way to do. Good luck!