It is actually allowable for people to get different things out of a television show. Just because, for me, Rose Tyler is the love of the Doctor's life, doesn't mean that a) she has to be for you or b) that believing that the Doctor had and lost the love of his life will suck the joy of the show for me. Which, incidentally, it hasn't. I actually really enjoyed S3 (some episodes more than others, but on the balance, quite a lot).

You may not feel that there's any point in watching a show where the main character had a 'love of his life', but I (quite obviously) feel differently. I also quite enjoyed the Bourne movies, where Jason fell in love with Marie in the first movie, lost her and then (quite pointedly) did not fall in love with Nicky in the third, despite there being a clear similarity in the situations involved.