Husband has a chequered history with female colleagues and has now hired drop dead gorgeous assistant manager, it's driving me insane? What do I do?

Married almost 19 years. 9 weeks into our marriage husband was tempted to cheat with an ex who was back in the country on vacation. Basically he was out with his best friend, met her in a pub, ended up going back to a house with her till 5 in the morning. When he came home I had a strong feeling he hadn't been at his friends house like he said, so checked phone and there were missed calls and messages from friend saying please go home, please you are married. My heart sank. Asked him the next morning, continued to lie, told him I knew the truth, and had called his best friend who said yes they were flirting with each other and he did beg him not to go in the taxi with her. Well he did, and spent about 4 hours with her. Told me they chatted, nothing else. I couldn't prove otherwise. But I did make him leave for a week while I decided what to do. Decided to give things a go and try move on. A few things though. One, about a year into our marriage he said he was going out to meet his friend, just again got that feeling he was lying. So again checked phone and low and behold messages inviting him for drinks from a woman he knew through an ex colleague. Barely knew this woman but they apparently bumped into each other that day. So, his messages back to her were deleted, questioned this, and he played dumb, said he didn't meet her. Wasn't happy but tried to not dwell. Then a case of colleague mentionitious, like couldn't talk about her enough. She was the dogs danglers and all that malarkey. So of course it made me a little uncomfortable. Particularly when they were away at a work conference with dozens of colleagues and they decided to have drinks a dinner alone. I hit the roof when he got home and demanded to see his coded work phone. Many messages with flirty undertones from her, ie selfies inviting him for drinks when in our town Then another colleague who he hid friendship from me. And now the insanely hot assistant. What do I do? So many lies over the years

Husband has a chequered history with female colleagues and has now hired drop dead gorgeous assistant manager, it's driving me insane? What do I do?
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