How do you know you are no longer in love?

So my BD n I have been together for a while but the past couple of months have been really bad. I started falling out of love. Right before new year's I ended things completely. I put myself in a mind state to move on. After I couple weeks we decided to try n fix things. But problem is im not sure if I love him anymore. And if I don't then can I again? There are a lot of burns from the past but I want to be with him and fix things. But things that I didn't do before like talk or even think about talking to other guys seems so easy to do now. How do ik I don't love him? And will I be able to love him again?