Imagine if this was the other way around and you were the one sleeping with someone else while your wife is at home pregnant and looking after your child. Do you think she would be nice about this? Would she try to understand? Try to forgive? I know i wouldnt. Id have to stop myself from killing him stone dead...
It doesnt matter that this guy is old. That dlesnt make what she did any less bad. Shes asking permission to continue sleeping with him! Jeez man pack your things and go to your parents.
If you want this to work, you have to make her beg for forgiveness, beg for counselling and swear she will never even smile at this man again. The only way to show her your not gonna put up with this is to leave. Take control. You will then have all the power when she comes crawling on her hands and knees. She needs to be truly sorry and needs to understand the pain and destruction she has caused before you can even consider taking her back
"Don't ask a question if you can't handle the answer".