will he stay with her or decide im the one he wants

I am a 48 yr old snake. Mt ex befriend is a 44 yr old rooster. His new girlfriend is a 31 yr old tiger. She is young I am four years older than him. He wan't as honest as his sign claims. I found out he was sleeping with her. But only after months of doing so. Will he stay with her or decide he wants to come e back to me?