Since then (and since One Direction has been on hiatus), there has been a steady back and forth of shade thrown between both parties.
At one point, Zayn admitted he didn't buy the band's album Made in the A.M. But let's be real. We're sure he secretly downloaded it as it was FULL of bangers.
In a newly published interview with Metro UK, Loui was asked if he would ever forgive Zayn and possibly have him rejoin the band for a reunion.
"I just don’t think I am mature enough, even in my own head, to give that a real answer," he replied.
The "We Made It" singer continued: "At the moment, I am still pretty mad about the whole thing. I don’t think he handled it very well. But never say never. Who knows? He chatted a lot of sh*t in the early days. I thought One Direction were pretty good."
While there has been a lot of tension between these two in particular, Louis' loss of his mother in 2016 did bring hope for the pair to reunite.
Louis revealed that his mother, Johannah Deakin's, "dying wish" was for the boys to makeup and to "get back in contact with Zayn" because "life’s too f*cking short."
Louis admitted at the time that he and Zayn were actually on good terms, however, the "Pillowtalk" singer failed to turn up to Louis' first performance after his mother passed away, turning their relationship bitter once again.
Louis said: "I had a couple of calls with him after I lost my mum, and all the boys had agreed to come to that performance, and he didn’t show, so that really bugged me…
"It was just seeing everyone there—Harry, Niall, and Liam—that was what I needed that night, that support. So on the other end of the spectrum, it kind of really showed. So, eh, I hope he’s alright, but…"
Recently, Liam Payne has been making comments that have fans believing that he and Louis aren't so close anymore either.
Aside from actually admitting that he and Louis hated each other when they first started the band, he also claims that he has no reason to stay in touch with any of the band members anymore.
"I keep in touch with most of them. I think other people just want their space," Liam told Wired. "And also, you know, we worked together for five years. Some of us, we didn't really have that much in common except for that we had a job together. Now that we don't have that job together anymore, there's not really any real reason for us to talk that often. Which is fine. That's just the way people are, really."