I need to decide to stay or leave or if I am plain fucked.

I am 32 and have three children under four with a woman is 24 all of the children are mine, we rent a home, and I am the sole bread winner.

To say her behavior is anything less than disrespectful anymore would be a compliment, but recently she started going to her moms or being busy constantly, and I had this weird feeling in my head her ex boyfriend was in town yet he lives five stats's away, two days ago I walked into my local gym where I train routinely and this dude is there (weird af) he stares at me, and I ended up following him to the other side of the gym and he acted like a complete pussy and got me banned from my gym.

I have this weird feeling in my gut she fucked this guy, as a week ago she randomly trimmed her oussy and butt area which she never does, when I seen this I got the weirdest feeling in my whole body. Fast forward since this has went down at the gym, she Trieste to among me, I been sleeping in a separate room of our house, we were supposed to be going to Las Vegas, but she threw a tantrum in Colorado and I turned around. I have around 13k in cash and a 1000 dollars in plans gift cards for southwest. This chick acts more disrespectful since I been sleeping in my own room and keeping yo myself calling me immature, telling me I need to man up, this is redixidulus, and a host of other shaming tactics, and acting insane. I know she won't admit to any of this, but something's obviously up.