Girl Opens Up:"I’m Sleeping With My Boyfriend’s Father But Don't Know How To Tell Him"

Dear reader,
This message was sent to us by one of our numerous readers, who wants some advice desperately as it concerns her future....
Read her story below;

Something is happening between me and my boyfriend’s father that will come out soon but I don’t know how to present it to him, because he may not forgive me and even attack me, am really scared. Please I want you to share my story with people so I can get good advise on what to do and how to do it. My boyfriend is stingy but I love him.
He is always doing projects and will say he needs more money for his projects. So, one day I met his father at a hotel where I went to do supplies: Since that day my life has not been the same again. The man has been spoiling me with cash and I have been bedding him, not that am proud about it but I need money and my guy is not helping.
The problem now is that his father wants to marry me since he is separated from my guy’s mum and he said I should forget about his son, after I told him about us. He told me his son is not responsible. Truly, I love the father more than his son now.
But I’ve dated my guy for 10 months and most of his friends already know us as lovers. Pls my headache is how to tell him about me and his dad and our intentions to get married without getting him too angry that he will do something bad to me?
I want to go to his house and tell him. Please help, i don't know how to go about it!