I'm going to come between my wife and her former friend.
Why would you want to come between them?
It's just best she gets over him.
It's good that you want to protect your wife, but you don't have the right to tell her not to talk to someone. If you feel like she's putting herself in a bad situation, you should have a constructive conversation with her without giving her ultimatums. If you try to get in between her and her friend, you'll only make her resent you.
We have an arranged marriage so it makes me feel insecure. I should tell her how I feel right?
I am sorry that you are not feeling secure in your marriage right now but it is wrong to get in the middle of their friendship. You should talk to her about how you feel so that you both can set up some boundaries to feel more secure.