I understand why this book was so scandalous at the time it came out. It dared to voice the fears of many women at the time (I would go so far as to say the majority of poor and working class women). Emma, while not a likable character, was trapped by society's expectations, which to some extent makes her sympathetic.
She thought she wanted to be married based on what society dictated a gently bred girl should do. The reality of her married life made me think of a line from Thomas Hardy's [b:Far from the Madding Crowd|31463|Far from the Madding Crowd |Thomas Hardy|https://d.gr-assets.com/books/1388279695s/31463.jpg|914540], when Gabriel Oak initially tries to convince Bathsheba Everdene to marry him. He described what their married life would be like thusly: "And at home by the fire, whenever you look up, there I shall be—and whenever I look up there will be you." I remember reading that line and being horrified by the prospect. Sadly that was likely what the reality of married life was for the majority of women. Yes, Charles was a good, decent, hardworking, honorable man who adored Emma. But unless a woman is head over heels in love with her husband (and I imagine it helps if she's a little short on intelligence and imagination), such a life would be unbearable! Thank God society has changed.
And really, it all boils down to the fact that Emma just didn't want to be married. She wanted romance and passion. While her husband was very much in love with her, he was quite incapable of the sort of passion she craved. When someone else offered it, she was all too willing to allow herself to be seduced. Obviously, such behavior was totally unacceptable at the time. Even by today's standards, there are a myriad of unflattering appellations which would be used on a woman like that. Easy, slut and loose are just a few of the less offensive ones. Oops! Did I say society had changed? Obviously, not as much as we would think. Women are still judged more harshly than men.