Well love is mad.
You should really share some of your time with you. Why MSN or SMS?
Why not call and listen to the voice? Its more intimate than pure
text I think.
Not that you're in the wrong to be busy. But it might be way too
much.
But remember in a marriage, as much as you're an individual and
needed your own time. Remember your vows that both of you belong
together and to each other.
Imagine you're in his shoes and you love your wife, but you can't
see him, talk face to face etc.
Not saying you're in the total wrong, but I guess he's still crazy
about you becos' he loves you.
1) Talk to him. Ask him what is he thinking and understand.
2) Tell him about your situation and then make sure he understands
too.
{Please don't do (2) and then do (1). Follow order.}
3) Both of you try scheduling your time to make time out for each
other. Please do something which you have common in him.
4) Seriously, you're making him really insecure by not allowing him
into your "personal" life with your friends. Remember you're
married and you should share each others' lives now.
If you don't really want him to be around you with his friends, at
least talk to him about the activities you did with your friends.
He might become interested and want to join you all.
By denying all information, you're really on you own. And
seriously, this marriage is doom to fail 99.99%.
5) Go travelling with another guy should be okay. But which man
would want to see his wife go travelling with another man when most
of the time he can't be with his wife? It would be very upsetting
for any guy, even for a woman in a vice versa situation.
Do you ever talk to him what you do when you travel with the guy?
Chat with your hubby over phone when you're overseas during that
time? If you did none of that, its really a dissappointment.
I kind of pity your husband.
You might say your husband should trust you as a husband. But trust
is nothing without proper communication. Don't let your partner
guess all the time what you're doing. It'll only drive him crazy,
cos' he as a husband would want to trust you, but no information
from you meant he could think of other things.
I hope all these advices help and I hope you would do something
about it. 
