If you’re getting bored, that means things have to change! There must be something missing that you want to do that is causing the relationship to lose its spark, but a spark is easy to gain back. All you have to do is regain some spontaneity, or go out more often, it could be anything really. Just try to change things up a bit and regain the excitement in your relationship. :)
P.S. You shouldn’t promise someone forever unless it’s in your wedding vows. It’s impossible to keep that promise because you never know what could happen.