Can someone who's a genuine good guy still be capable of abuse??

I judge people by my own behaviour and expectations. I manage not to abuse anyone. Therefore I expect others not to and if they do they are abusive. We all make mistakes but I think we all also have clear lines in our minds which we don't cross. Or some do of course, and you judge them accordingly. And avoid.
What sort of thing are you talking about op?

Nope

Is this your loser of a boyfriend? Just dump him instead of making semi cryptic posts, save yourself some time

People can and do often have a different public and private face.

No.

My ex in public is like the kindest gent on the earth

At work everyone thinks he is the finest man to grace their presence

At home he was A VILLAIN
A real awful abuser

People thought I was lying when I told them
Even my closest friends

Abusive people can con people into thinking that they're good guys. But truly good guys don't abuse people.

Same for my ex

No.

If you are abusive you are not a good guy. You could pretend to be.

No, abusers are abusers. Good people do not abuse. They do not hit, they do not force themselves on others, they do not belittle, they do not control.

Genuine 'good guys' are not abusive - end of.

This!

I have known a couple of blokes in my time who had the lovely guy act absolutely perfected. I was totally shocked and blind- sided when I discovered what they were really like.

They were both abusive to their partners.

The nice guy act was just that, an act.

Mistakes yes, proper abuse, no.

I mean I consider myself to be a "good" person, but in the past I have made bad mistakes eg I've let lust get the better of me, cheated in a relationship, and hurt (ex) partner as a result. I feel bad about it all the time.

The reason I still classify myself as a "good" person is admittedly still up for debate! But I suppose I never, eg, deliberately belittled my ex partner, stole from him, threatened him, made him feel afraid or intimidated, you can't do those sorts of things as a "good" person. It's not in you.

No.

No, is the short answer.

And if you have to ask you should really rethink your boundaries and expectations. Really do.

If you have been dating some one great who has lashed out due to a sudden mental health issue or similar leave them to get themselves sorted. Sends a clear message about what being in a relationship with you entails.

But keep in mind 2 things:
1) no one who commits DV or any other abuse, does it on a first date - they hook you in first.

2) use some common sense - I have never and would never abuse someone, if I did as a one off when really I was genuinely a good person, my response would be mortification and immediately separating from that person while I prioritised getting help and support for my MH. It wouldn’t be to carry on dating that person, or expecting them to date me, without working out what the fuck happened to cause me to behaviour in such an obviously unforgivable way.

Give over

Stop looking for excuses to stay with an abusive man

My guess is OP is actually friend/sibling/other close rellie of the abuser clutching at straws in a desperate attempt to excuse the inexcusable.

No.

The other way around definitely yes: can an abuser be a really nice guy in public and to others?

No and what a strange question, isn't the answer blindingly obvious?

Abusers are charmers, that's how they can abuse because everyone around them thinks they are a lovely person, often including the victim.

Personally I wouldn't call an isolated incident abuse. Not that an assault or an incident of upsetting nature is ok.

What kind of isolated incident @Bubbles1st?

Yes.
But that doesn't make it ok or better.
If anything I would say that the abusers who set out to abuse deliberately have some kind of personality disorder that they were either born with or have no control over and don't actually feel any empathy or so on for their victims, they just feed off the response that they get from the abuse!

But the other abusers are probably normal people without personality disorders...who could probably pinpoint the reasons why they do what they do if they went to therapy, they do know that what they're doing is wrong but more often than not they don't go for help to try to control their own behaviour and deal with the triggers that cause them to abuse.
I read an article before about reformed abusers. They got help and no longer abused their partners, but generally they had to end the relationship first and get away from their partner and learn to stop the behaviour on their own.....so if you're the partner of someone who abuses you and you want to stay with them because they've promised to change and stop then please know that generally those people need A LOT of therapy and can't stay in the relationship while trying to fix themselves!

Of course it's still 'bad full stop'.

Abusive behaviour is abusive behaviour.

There may be reasons someone is more likely to be abusive, but none of those reasons make the abuse acceptable in any way.

There may be people who behave abusively who don't think they are doing anything wrong, who cannot understand why their behaviour is abusive. None of those reasons make the abuse acceptable in any way.

The only amount of acceptable abuse is none. Zero.

Good people do bad things. Some good people may do abusive things at certain times in their life. The abuse is, as you put it, *bad full stop" and completely unacceptable.

It's worrying you are trying to decide this. It doesn't matter if someone is good / bad / all the grey areas between. Abuse is abuse and is totally unacceptable.