He Vents to Another Woman

I'll preface by saying they claim to be friends. I'm not the type to believe men and women can't be friends. I have male friends that things have never surpassed a good laugh over drinks and going home!

However, I never knew about her until a couple of months ago because she called him late at night.

He claims she's just his friend and that sometimes he vents to her about me telling her when I am being "crazy"... I.E when he suddenly decided to start coming home late a few weeks ago.

Anyway, I called her myself and she claims to not have known about me. I just simply told her that I have no issues if they are truly friends. I just don't like the sneaking! Well, she then blurts out that he has been at her house during all kinds of hours and even met her family. Attended a few family events with her last summer!! My heart sank! But then says that they are only friends.

Well, he promised to cut her off. The story didn't seem right. I found out a couple of nights ago that he's been talking to her again! He changed the name in his phone but I recognized the number. I text her asking if they spoke and she acts surprised and says he told her that we weren't together anymore since a couple of months ago when she called at 1a.m. She apologized profusely and promised to cut him off.

My thing is....a simple friendship wouldn't be this complex. I have no issue with her, hell I don't know her. But he swears it's just a friendship.

I don't want to sound stupid or naive but......Be real with me?! Am I being crazy for suspecting that there is more to this "friendship"?

To add: I was asked if we are married...No. engaged. We have home together as well.