Is it wrong I didn't feel bad about cheating on my ex?

[Medeguy]

2 years ago when I was 36, I had a 6 month sexual affair with my 19 year old co-worker. I wasn't happy with my relatinship. She was 10 years older than me and I didn't find her attractive anymore. My co worker was slimmer, more fit and had much nicer skin complexion. Our sex life stopped because I wasn't interested in her even if she was. She also treated me much better. I was the one who initiated our relationship and we had great time together. I broke up with my ex eventually, told her I need a younger woman, but I never told her about my affair. 

I never felt bad about it, because I feel its more acceptable for a man to cheat than a woman in these cases when it involves sex. I feel if she did that to me with a much younger man, it would be much worse because women should control themselves sexually. It definitely makes a woman look bad in my opinion.