is he cheating.

ok I have never caught my husband cheating but I have so many suspicions sometimes. when I was preg. there was this girl who liked him and always has. and he told me he wasnt talking to her. I decided to check the phone records on the tmobile website and I found that he was texting and calling her as soon as he woke up in the morning, all throughout the day, and the last calls would be on his way home. but everynow and then she would call late at night. and he would never answer her when he was home. then I found messages that he sent to her asking her to come over naked with only her high heels on. yesterday I found messages on his myspace inbox/outbox telling this girl we know she has a nice booty and to call him sometime that what her boyfriend doesnt know wont hurt him. he says he was playing and sees nothing wrong with it. and this girl from work calls alll the time and she claims to be my friend but she always calls for him. and the list just goes on. what do I do? what do I think? I dont want to be mad e a fool out of. when I stay home everyday all day with our daughter, cooking, cleaning, and doing his laundry, ect.

I need advice.