Is it cheating ?

My husband had an online "thing" with a woman he met on a game he plays. They all gather on an app and have voice chats. I found messages between the two of them flirty and twice she sent gifts to our home with a note which he said were just "friend" gifts. I ended up telling him I saw their conversations and that I know they talked online other way & they probably had sexual exchanges though he denied that part. She lived in another country so I know that didn't happen but I don't doubt it would have if she lived here. Granted we were not on the best terms at that time but I kept telling him to leave and he refused but then carried on with that crap. Anyway after I confronted him we moved on. He still plays this game and I decided to check his messages and today I found messages with another woman as far back as last year when he was taking to the other one and she asked him if he was still "with" her and that the "cyber sex" could only go so long" and other things he said he "ended it with her" and had been behaving because we decided to work it out. Meanwhile he is messaging this one as recent as last month with "sexy can't wait to hear your voice" "babe" and other inappropriate things though not blatantly sexual but I know they all voice chat and God knows what else. I'm actually like WTF. Is this "cheating"? If I was like bro get out you lied to me am I crazy? My friend said I should separate or divorce I hate to break up my family ( we have two young kids) but to me I'm being disrespected after I was the last time and I don't wanna just pretend anymore. I just don't know what to do next! Help! How do I proceed and should I? <3 I only told one other person and I don't know what else to do.