I had recently come to know that my husband has been chating with a known woman and I came upon the text messages which said he missed her and called her love. I have started to doubt their relationship but he denies by saying it is only on the net.how do I believe him? I have started to feel jealous and insecure.Please guide me

Those are real people on the Internet (just like you and me). Trains, cars, buses, and planes can bring them together in person.

What he is doing is harming your marriage. Will he go with you for couples counseling?

Chatting with known friends, I feel, is quite safe... however, him telling her that he misses her and calling her pet names, is not so safe.

Calling her love!! You should be more than just jealous and insecure!! Try calling some person "love" and let your husband know. Then see what happens. As for the believing part.. the signs say not to.