A former colleague of mine once had three girlfriends on the go simultaneously and in fact two of them did have the same name! He didn't quite manage the trifecta. Not surprisingly, the one with a different first name was the first to twig what was going on....
In a similar story, when I worked for the nationalised offshore oil company in Abu Dhabi, there was a legendary British expat working on a platform in the Persian Gulf who convinced his wife in Britain that he worked three months on and one month off whereas in fact he worked one on one off. He found himself a second wife in Thailand and convinced her of the same. For ten years, he got away with this classic bedroom farce. Everybody in the company knew the story. His back to back, if quizzed about his colleague's whereabouts by one of the two spouses, would always respond with, "oh he's on the rig somewhere, I'll find him and get him to call you". He'd follow that with a quick call to wherever his colleague was currently holidaying saying that he needed to call the 'other site'. Then one day, his back to back retired and there was inadequate time for a proper handover with the replacement. Off he goes to Thailand in the middle of the UK winter. Pipes freeze in his UK home then thaw - result water everywhere. UK wife rings up the rig and the new back to back, the only person in a company of 5,000 people who didn't know the background innocently replies "oh, he's in Thailand with his wife"!
The two wives did not have the same first name... nor the same husband after that!