You have to offer an image of looking forward and seeing the past in a positive way. So you can use phrases like, "I've learned from this experience and...." or "the benefit of me taking this course was to discover that I this subject was not for me but ..... was".
Home stuff and the mental limitations that this can impose on you, i.e. reduced bandwidth due to stress. You could talk about the learning experience of handling stress and development, but it would require a clear positive image that such problems are in the past and will not happen again.
Also you can explain this by saying that you've been always interested in this kind of work and now is the time to make a move. I mean better late than never RIGHT!
And in my opinion; unhappy private life reasons could be taken positively by employers, Because it shows the real desire of changing.