Reconnecting with an ex boyfriend

So my ex and I of about a year broke up 3 years ago. I was starting the hardest part of my grad school journey and he had just joined the military and was struggling to adapt. We broke up simply because we could not devote our full attention to a relationship (and we lived in different cities so travel was kinda hard). There was no malice in the breakup. Fast forward I'm wrapping up school and he is way more settled into his life and we have reconnected and it has felt nice. I'm obviously cautious but most people say going back to an ex is terrible. What are your thoughts? Am I crazy for revisiting this.