There's a fallacy spread in our culture that says that there's a prince charming for you somewhere, and while that may be true for some, the fallacy extends itself by saying that you won't be happy until you find him.
Love, in my view, is more of something you build that something you find. My man and I are not "perfect" for each other in many ways, but we have experiences from being together a long time that I'll never be able to replicate with someone else.
Love becomes mediocre at times. The honeymoon period ends, and you're left with the day-to-day drone of real life, with passion merely existing in the background. This is normal and healthy. There will be periods where you think you don't feel anything for him, because humans naturally become conditioned to sensory input over time, as well as emotional input, when it becomes a constant.
Long-term love becomes something you don't appreciate until it's gone. Monogamy can get boring, everyday, mediocre, but appreciate that you have that luxury. Appreciate that love is so abundant in your life that it becomes like breathing. Don't take your boredom for granted, the reason couples stay together so long is that they don't up and leave whenever things get mildly inconvenient.
Don't relentlessly search for something better, because chances are you'll never have what you do now. There is value in something you've built with someone over such a long period of time you begin to take it for granted. Instead, focus on ways you can get that spark back. Continue building that love by having new experiences together. Travel, go rock climbing, experiment in the kitchen, try a new sex position. Love is not worth losing over boredom or the possibility of "more" being out there.