So what would be enough evidence to corroborate her story?
There are all sorts of mean things you can do to another person when it’s just the two of you that, should the other person pursue legal action, would have no chance whatsoever in a court of law. Civil court is another matter. They can be all over the map, and often are.
What kind of physical evidence would indicate that a gun was pointed at her?
Also, regarding the table: She said he smashed the table. The table was smashed. It’s too early to say whether that’s enough (as you note, he may have some other explanation of how the table was broken), but the broken table would tend to corroborate her statement. Are you saying that accusactions of breaking someone’s things are only actionable if those things are hard to break?