@Welshie2 I am really sorry for all that he has done to you, this chaotic behaviour must be so confusing on top of that.
He is lurching from one mess to another...he conducted (at best) an emotional affair but lord knows if that was just the tip of the iceberg. Blamed YOU for the betrayal for looking at his phone, stormed off and gave himself time to think/react to it all.
Then he has blamed this junior colleague, which, let's face it, is also rubbish because if he really was as put out by her behaviour as he claims, he would have gone straight to HR and reported her! Instead, he enjoyed the flirtation.
Then, instead of apologising for all he's done and talking things through with you, seeing what YOU need, he books a holiday he suddenly can afford after years of not being able to... and he thinks it's appropriate to buy sex toys and chairs. Like anyone would even want to go near their cheating spouse like that after he'd been chasing after another woman like that.
This whole thing has been about his wants, his needs, his desires. He's giving you emotional whiplash in the hopes you stay with him and let him get away with it. This is so utterly manipulative that it's making me feel sick.
Op, you deserve so much better than this. None of this behaviour is ok. He is showing you that all along, he could have paid for holidays, he could have 'spiced up' your sex life, he could have been attentive to you.
Instead, he is using all this as cover to shield his awful behaviour and coerce you into staying.
I can't imagine how you must be feeling but I just couldn't trust this man. He's showing you who he truly is: please believe him.