How do I break up with the love of my life?

I love my boyfriend and we’ve been together for several years. Lately we’ve been having a lot of problems and I’ve been questioning our relationship a lot. I do love him, none of those feelings have changed, but I’m worried it’s one-sided. I’m not that happy anymore and something feels like it’s missing. Is there any way I can salvage the relationship or is my best option to just end it? Any idea how I would if i needed to result to that?