I (39m) and my wife (40f) have been married for 17 years next month. We have one 15yo son and have what many would consider a normal, good marriage. We both have good jobs, our son is a great kid and we are active romantically and communicate really well. 

Around 2020, my wife, while drunk, came out to me as a lesbian. She assured me that she did not want to end our marriage and that she only wanted to explore this side of herself but do so in a way that didnt hurt our relationship. She was accepting and understanding of my feelings and while I definitely struggled, she was kind and communicated really well through it all. That same year, she developed a small crush on a semi-acquaintance and she expressed that she did want to explore the possibility of opening our relationship so that she could have a sexual encounter with that woman to experience it. After communicating fully, I was on board but after a few attempts at flirting/etc - nothing materialized and the topic wasnt really discussed. 

In those 3-4 years, our marriage remained strong, we had regular sex and were very affectionate and supportive. We just never revisited the situation - while understanding her sexuality was what it was. 

Flash forward to this year - My wife and I regularly socialize at a local LGBTQ bar and many of our friends are from the community. My wife has mentioned previously that she finds one of the lesbian bartenders attractive and expressed a renewed interest in exploring her sexuality with this person. 1 week ago, my wife was at the bar without me and end up connecting with the bartender and they began text messaging frequently. My wife was very up front about it with me and we have had several conversations about what she would like to explore, what this person thinks, my feelings, etc. As we have continued to have those conversations, I have been supportive and tried to balance my fear of loosing my wife and my wanting for her attention with the idea that I am doing the right thing to support her in discovering this area of her life. She continues to reassure me that she does not want to end our marriage and that it is "not that serious". 

But now I am spiraling because last four days have been a whirlwind. My wife's communications with the bartender have been moving very quickly and their flirty nature has developed into a physical one with playful touching in public and as of last night, a sexual encounter (not full sex). 

 She continues to say she doesnt want to leave me and end our relationship but that as of this morning, she "could" see herself in a relationship with this person and is scared that she "could" see herself falling in love with them. 

My question is this:

Is It fair to ask her if there is anything we can do as a couple to NOT go down the road where my wife opens herself up to the possibility of a relationship or falling in love with this other person? 

Im willing to put in the effort to help her understand her sexual desires. I also recognize that my wife isn't just trying to have sex with a random person but also I want to do whatever I can to limit an emotional bond to develop that would end my marriage. 

Will loving and supporting my wife's needs here end up pushing her away from me and causing me to lose her? 

Please any help/advice folks can give me would be so appreciated. Im struggling so bad and just want my amazing wife back.