<human>: Can you summarize the given text in a few sentences?

I am apologizing in advance for any formatting issues as I'm on mobile and the wall of text. 

Backstory:
I met my amazing wife in March 2013, it was my 2nd marriage and we ended up falling hard for each other and were exclusive within a week and said our "I love yous" in two weeks. We got married three months later in June 2013 and have been very happy since. 

Like all marriages we have our ups and downs but we communicate well,  share each other's hobbies and have a great sex life however in the past few weeks my wife has causally mentioned a few things that make me uneasy. 

A few weeks ago we were talking about why her ex-FWB (now friend) had cut off all contact with her. I am fine with the guy even though my 1st marriage ending up failing due to my ex cheating on me with a Ex-FWB. As we are talking she says "You know I slept with (guy) on (xx/xx/xxxx)?" which coincidentally was the night I asked her to be my GF. She has always been open about her relationship with him and shows me their texts (even though now he rarely responds) So I am not worried that anything is happening with him but I was still taken aback by the comment. 

She has also mentioned on a couple of occasions that she regrets getting married as quick as we did and that if she had talked to my mother more about me she wouldn't have married so quickly. When I press her she tells me that she has no regrets marrying me and nothing is changed as far as our relationship and sex life. 

I don't know what to do at this point as she says everything is fine and shows it, I trust her around her Ex-FWB (I admit a part of me is relieved he has gone NC for whatever reason) but her comments, as causal as she seems to believe they are, have me uneasy.
<bot>: My Wife casually mentioned she wishes she didn't marry me so soon and that she slept with someone at the beginning of our relationship but doesn't seem worried about it.