Is he ashamed of me??

I am a 42 year old woman married for 18 years. Fairly attractive..friendly, outgoing. My husband is an introvert, workaholic but a decent man, loving father but like most men falls short as a good husband. Now, the problem. He doesnt like me knowing his co-workers - male and female. Everytime there is an official program where the wives are invited, he doesnt take me with him. He always comes up with some excuse...tells them that i am sick, out of town or something. Recently there was a huge party- a family day celebrated in one of the beautiful and expensive and exclusive beach resort...which we can not dream of going otherwise. I was very excited and very much wanted to go. Till the last day, i was telling him about the dress i was going to wear and asking him if i needed to bring anything and generally talking about the outing. The next morning, he woke up my kids and asked them if they wanted to come for the party or stay at home with me. I was like, arent we all going? He said, no, its ok, u stay home and rest..i will take the kids with me. I was soo hurt that i kept quiet and watched them go.
This incident set me thinking, this is not the first time this has happened. Some of the family events, i have not been aware of at all...some others, he had not taken me. I have never met any of his colleagues except by chance in some mall or supermarket. Whenever his colleagues invite us for their homes or parties.. he goes alone or takes the kids along. When i want to invite them home, he says he will entertain them himself in some restaurant...and i need not tire myself.

Is he ashamed of me? What should i do? Please help. thanks

 

Thank you. It is indeed strange because otherwise he takes me out for lunch, dinner, malls, movies etc., always as a family...just the 4 of us. But he doesnt want me to meet his friends or colleagues. In the years we have been married, he has never taken me to any of his offices...he has changed quite a few jobs but i have never met any of his colleagues socially. I on the other hand always introduced him to my friends and colleagues (when i was working) I was perhaps naive not to question this behaviour before, but this time, he knew how excited I was about this event., and his refusal hurt me and humiliated me. I texted him asking him if he was ashamed of me and was that why he refused to take me., he didnt respond and when he came back home, he was acting as if nothing was wrong. I texted because if i had spoken to him directly or over the phone, i would have burst to tears and humiliated myself further. Now, we are not talking to each other. Dont know if i will ever get over this hurt. My older one is aware., and had asked my husband why you dont want mama to come. Apparently he said that i deserved rest at home after all that I do. I am a sahm, and have lot of time in my hands and more than adequate rest...what more rest do i need? He made me sound as if i was always sick and bed ridden