Like the comments say, it'll take time and persistence -- especially if y'all aren't in a country where you're surrounded by 90%-95% spoken English.
The best advice I can offer from my own experience learning my second languages is, as soon as she makes an error, correct her on it. It may get obnoxious, but if they're cemented into how she uses English, then there isn't a quick fix. Of course, it would behoove you to sit down with her first and talk to her about it so that you don't get the cold shoulder or end up sleeping on the couch after the first day of being helpful. :)
A lot of it also depends on her own feelings about it. It'll be easier for her to break the habits if she recognizes them and wants to get over them; if she's satisfied with her level of English ability, less so. I cared less about how perfect my Chinese was and more with how fluently it came out when I was just starting to learn it, and would more or less shrug off small criticisms as I got them. But once I had a solid foundation in the language, it became a matter of polishing the language -- I wanted to be good, not just competent. Same thing with Spanish. But then, I'm a big language nerd who uses his language skills to pay the bills, so I'm kind of emotionally (and financially) invested in it.