I've been in a relationship for four years. We're engaged and live together. My fiancé is my first and only relationship and he told me that I was also his. Recently I discovered that this wasn't true and he in fact used to date someone else when he was at university in 2014. The relationship lasted for 9 months and ended the year before we got together. I found a picture of them, gigs that they went to and messages he sent. There was also public things on his social media. He told this girl that he loved her, took her to places that he's never taken me and also called her by the pet name he now uses on me. People who we mutually know also knew about it. I confronted him about all of this and he told me that he never loved her, she was a user and it was never a proper relationship. I understand and accept all of that to a degree and even the fact that he hid it from me, especially if it was meaningless, but what I can't get past is the fact he has told someone else that he loves them. When we first got together and he first said I love you, he said "you're the first person I've ever said that to". Now I know that's not true a part of me is really hurt. Particularly the fact that he even called her by the same pet name that he calls me. I accept that people have a past and I don't have a problem with that but for someone to say that they've never had a relationship before, whether it be a good or bad one when in actual fact they have and they've said the same things to them that they now say to you, is the part that I can't process. I love my fiancé with all of me and I truly believe he loves me but I just can't fully understand his behaviour. Any thoughts would be appreciated, thank you.