Neil house

Hi I have a 208 XF with the same problem ..the NS or passenger output shaft seal leaks. It has had a total of 5 new seals over the last 6 years with regular topping up and still leaks. I have tried jag seals and pattern seals as well as sealing the oil sea in the diff housing but still it leaks. I love the car but I am now considering getting rid of it. There must be a way o overcoming this Please help .