<human>: Provide a brief overview of the text.

I cheated. I got caught 18 months later. It was not a long term affair and I wasn't in contact with the other woman but I was still emotionally distant from my wife and would have cheated again given the opportunity. 

After she confronted me, I denied for several weeks before finally admitting to everything after she had basically figured out most of the details. We've been working through things and there are good days and bad. I've re-engaged at home which she has noted and appreciates. 

Every now and then she will send me an email calling me names, telling me what a terrible person I am, how she is losing it. I understand why she feels those things and accept that there will be ups and downs. But, I'm not sure what to say anymore. I feel like repeating "I'm sorry" is beginning to get repetitive and isn't enough. When I try to add more than that to explain my motives or my thoughts, that doesn't help and the fight gets worse. 

I'm hoping somebody has gone through this successfully and can offer practical advice on what I could be doing better.
<bot>: Looking for advice on specific actions, behaviors, etc. that can I can do to help my wife as we are trying to save our marriage.