The first thing I would do would be to try to always refrain from any kind of retaliation, correction, scolding, argument...anything negative. To do anything like that could likely just reinforce whatever fear she might have. So overall, I would try to wait for her to hopefully eventually say something on her own about her occasional outbursts and then only ask some non-confrontive questions about what she might think you might be able to do that might be helpful in relation to them. However, all of that does not mean I would just quietly stand there taking regular beatings. An outburst of anger about one thing or another is one thing, but an actual attack upon my person is never a tolerable action. "Get me once, shame on you; get me twice, shame on me."