I agree with @elijahsuicide. My ex-husband went through what you’re going through, but with me. Did that sentence make sense? The girl he was engaged to before me cheated on him repeatedly and with his brother. So while we were married, he was super paranoid, even though I never gave him reason to be. It sort of made me feel like, “Well, if I’m going to be accused for it, I might as well be doing it”... but of course, I never did. I just thought that in my head. We ultimately got divorced, for other reasons, but he was never able to let go what she did to him.
My advice might be to not vocalize every single worry or fear that you have. That will just make her feel guilty for going out with friends, even though she has no reason to be. Give her the benefit of the doubt. Maybe if she goes out with friends, call one of your buddies to watch a game on TV or something like that. Do something that will keep your mind from wandering while she’s out. When she gets home, ask her if she had a good time, but don’t get too detailed. Don’t interrogate her, you know? Then she might get defensive and will start hiding things from you.
Oh, and finally… Don’t do what my ex would do: We would be out somewhere and guys might stare at me or say hello or whatever. Instead of taking it as a compliment (that obviously they thought I was pretty) and letting me handle the situation by telling them I was married, he would get all macho-man and kind of bow up and give them the “get your eyes off my wife” stare-down. It was utterly humiliating and soooo immature. Please don’t do that to your wife! You said she’s beautiful, and she’s going to be looked at by men and possibly even be approached. Let her handle it. A woman of integrity will be quick to let a man know she’s taken.
Good luck!!