It sounds like there is some need in your life that is not being met. This isn't necessarily a sexual need, but could be emotional. Do you desire more emotional closeness or human interaction and closeness? It is possible that these basic human needs are manifesting themselves in a sexual way.
This doesn't make you wrong or bad, but could be indicative of something that needs addressing in your life. Do you have a therapist to process this with?
I wonder if your wife would find it easier to understand if you tried to explain your behaviour with emotional honesty as best you can, and seek help from either an individual therapist or marriage counselor. Making steps to change your behaviour might help to show your wife you are still committed to the relationship and would also be a great first step in addressing your unmet needs in a healthy way.