Mental stress

Am happyly married and have a baby of 20 months. 3yrs of marriage. Me n my husband were in love during college days 5 yrs aftr so much of struggle we got married with our familys permission.we were veeeery happy. Now the issue is i am very possessive on my husband.i dont want him to talk with any other girl. I was not like this befor. Usually he dont get chance to talk with girls. He joined in a company where there was girls working in his team. He use to talk with them frndly in wats up n calls in front of me. I dont had any problem. I dont like 1 girls dressing and way of talking to him. She flirts with him n his colleagues. I told him not to talk to her. N he gets angry on me saying that he know his limits. He is in his limits but the way she talks n flirts disturbs me.she calls him for group outing like they r from childhood frnds. And my husband says i cant avoid her its just frnds get together. I had many boys as frnds n colleagues befor marriage i stoped talking to them coz my husband dont like me talking to guys. Now i dont like him talking to that girl n told him many times he says ok but wen she calls n msges he reply to it n talk to her convence her for not attending the get together and give her fake promises to meet someother time. Usually he dont convence anyone. I get angry wen he convenc her. Now we have so many fights n misunderstandings coz of this issue. He says i gone mad n over reacting n lost his peace coz of me. Which really hurts me n am not able to love him lik before. Please give me some suggestions.

Thank u sooo much for the reply. Jus 3 days before i found my husband also likes to talk to her. Even he has called her 2 times wen am not in home. They hav talked casually. But he has deleted everything before i see anything. Am really upset about this. He broke all my trust upon him. Am feeling like am done. I asked him about this. He says sorry will not repeat again. But am not able to trust him again like before. What should i do. Can i give him another chance ? Am not able to see his face. Please tel me something.