While I am glad you set some ground rules about money, her taking care of herself and a job search I have to say I am a bit surprised.
Bringing her a cake, flowers and a card was pursuit. She chose not to spend her b-day with you despite the fact you asked. She missed out and that is that.
There was no problem with a meeting about finances and child related issues but the b-day stuff along with cuddling and kissing was a big no no.
James, she took a call from the OM who she is in an EA with WHILE you were with her AND told OM she would call him back. That is beyond disrespectful and you should have firmly told her you were leaving as you have no intentions of sharing your W with anybody else on any level. Why on EARTH did you sit there while she told OM she would call him back then ASK about him?
It doesn't matter what she tells you. Cheaters lie and now your W is doing it right in front of your face. Unreal.