When is it ok for a woman to be in your husband's life?

I'm very worried about this and have been awake all night thinking about it.

 

When a new woman enters your man's life and texts/emails – is this ok?  Forgive me if this is long but I need to explain it a bit to get your help: my husband and I are happily married with 3 little boys. He is a physio and for the last few months has been away from home from time to time for genuine work reasons. He has been away more often in recent times. There is a group of people that meet up only at these events. In the last 2 weeks or so, I have been hearing a women’s name mentioned quite frequently – I had heard it a couple of times before but it is coming up more often and it’s now turned into a shorter version of her name. I was subsequently on his phone, checking if he had contacted his sister about something important that we had discussed (sometimes he needs a reminder). So I went on and saw that it hadnt messaged his sister but instead I saw that over the last two months, he and the woman have been messaging each other and lots of them. Not every day but quite frequently and more recently. I felt sick to the core and couldn't breath.

 

The messages are made up of things like: what’s happening, sorry I didnt see you before you left that last event, how are you etc.  In more recent messages they have been a little friendly flirty, with kisses (i.e. xxx) at the end of messages, and recently he has added kisses too (she started the xxx). She also calls him babe. On the message they were talking about a recent event and meeting up etc.  And when she didnt turn up, my husband messaged saying ‘you stood me up!’. I have asked him now a few times what he did that night – I was never told about the arrangement to meet her, on her own, in advance nor have I subsequently heard that he had planned on meeting her and was stood up. The following evening to that arrangement, he told me the work gang all went to this pub for a party. I specifically asked ‘how did you hear about that’ and he said just during the day with the gang. This is a lie as she had messaged him about this before arriving at the event for work.

 

So I then went to his email and found they have been emailing since April – not every day but 20 or so mails. (I might add that he initiated the first email after they met initially.) In one email, she asked about how his family were and he answered everything else in the mail except that question. There is absolutely no mention of sex or kissing or anything intimate so I don’t believe that their relationship is of this nature but I still feel hugely betrayed. 

 

Finally, he’s very irritable with me and the kids at the moment – only recently. He’s definitely under pressure with work but I can’t seem to say or do anything right despite doing everything in the house and with the kids to help him with his job. I'm not sure if they are linked but I thought I'd include it here too. I know he admires her work and that she is a very good at her job but I think it is strange that you can exchange so much with another women, and never have told me about it. Surely, if there was nothing to worry about, he would have said and wouldn’t have kept it quiet?  He has also just told me that he is working at an event in a few weeks and he has specifically requested her to be part of his small, currently man only, work team.  When I read the mails/messages, I felt really let down because I completely trust him and even if there is nothing sexual going on, I have a feeling of betrayal because I consider non-disclosed, secret messages and emails to be inappropriate. So I have a few questions:

 

1. Is it ok for a husband to make a new friendship with a woman?

2. Is it ok for them to be sending messages/emails to each other?  With kisses xx?

3. Is it ok to keep them secret and the meetings secret from me?

4. What should I do?  Bring it up now or wait until this plays out as it might just be nothing?  I have a feeling that the standard guy response in these situations is that ‘you are imagining things’ and reading more into the messages/mails than are meant.