Calling a partner who cheats an abuser is quite the leap.
There are remorseless serial cheaters for sure, and that is abusive and cruel behavior. There are also people who cheat because they feel like their needs aren't being meet and haven't figured out how to communicate that. And when that happens, there's three options: figure your shit out, learn how to communicate, and rebuild trust; figure your shit out, learn to communicate, and accept if your partner isn't interested in staying with you; or don't take accountability. I don't think any of those make them "abusers," even the last one which is quite shitty. It makes them a flawed human and someone who shouldn't try to be with someone until they figure out how to be better.
Edit to add, I was pondering more and there is a 4th option. I was thinking "don't take accountability and get dumped." But there is also "don't take accountability and your partner stays with you," and I would agree that that is abusive.
Probably depends a fair but on what else you eat with it. Like how drinking water doesn't help but milk does.