Should i trust him?

My husband is constantly texting a female coworker. We’ve been married 8 years and he’s given me reasons in the past not to trust him. His company recently has been searching to fill a vacant spot and he constantly talked about the search until one day he just went quiet. Come to find out they had hired a lady to fill the position and that’s who he’s been texting at night and on weekends. We have a 3 year old and 4 month old and he will make them wait to text her. He also goes on overnight business trips with her which he’s on this entire week and has led to a huge fight because he didn’t tell me she was going, only his boss and another coworker but she’s there. He’s very jumpy if i ever touch his phone and is erasing messages because he says they are just friends but if he’s texting any girl at all i will get mad even though there’s nothing going on. When i say anything he becomes defensive and says i don’t trust him and I’m pushing him away. No matter how many times i tell him it’s not right he somehow spins it back as being my fault for not trusting him and that he doesn’t have a problem with me texting guy friends. I don’t know what else to do or say but I’m at a breaking point! Help!