He's just not a great guy to anyone
Walk Out
Source: Instagram @realamberlportwood1__
Among the reports that he simply walks out on his romantic partners, he also walks out of work. He left his radio DJ job with no warning, and he even stole his on-air persona from another more popular DJ.
Pusher

Credit: MTV
Matt can talk his way into any woman’s heart and home, it appears. The way that he first moved in with Amber, presumably, was by saying that his lease was ending and he needed a place to stay one of the first times they met.
Cheating Ways

Credit: MTV/Imgur/CoCoPony1
While texts have come out recently that seem to show Matt flirting with other women in an aggressive manner behind Amber’s back, Amber and Matt have denied all of the cheating rumors.
But considering how many women Matt played simultaneously and got pregnant by him, I think it’s safe to say that Matt has been cheating on his women for most of his life.