Why would he text me out of nowhere?

I was kind of with this guy in high school from freshmen through senior year. We separated and stop talking because I was the one who was going far away for college, while he stay in the bay area. Our plan was to be in the same city, but I wanted to go somewhere else. Its been three year and now I’m back in the bay area for college. I don’t know if he no I’m back, but it’s just weird how he texted me out of no where wanting to know how I have been. It’s also a weird timing because I just broke off my relationship a few months ago and he just suddenly pop up.