OK, as আপনি already know, at the end of season 3, Ted proposes to Stella. At the beginning of season 4, she says yes. This leads to a few episodes where they are engaged, and Ted begins to wonder about the decision. Then, in the episode "Shelter Island" they have the wedding, however, Stella leaves Ted moments before the wedding for her ex, and Lucy's father, Tony. So she does say yes, but they don't get married.