Well, you have (no pun) seriously screwed-up. You only have two choices : (1) have an abortion (either telling him or not telling him about it) and (2) come totally clean about the whole thing: telling him absolutely EVERYTHING. Anything less than the total truth will backfire: I absolutely guarantee it. Then it is up to him to decide what to do: hopefully, he is a truly wonderful guy who can accept you AND another man's child. If you try the 3rd route: having the baby and trying to pull it off as his - the odds are almost 100% that , at some date, the truth will come out. SO, having totally screwed-up, are you a big enough person to NOT take a chance on totally messing up 3 lives ( his, yours, and your baby's) ?