My question involves defamation in the state of: Texas

I have a start up business. One of the verticals I serve is healthcare. My fiance is a doctor. He introduced me to a higher up doctor in his hospital and tried to help me get business. The first couple of meetings started well, but my fiance kept calling it "our business". it's not. And my co-founder/developer/initial investor became very angry that he was stating this. It got under his skin so much, he claims that is the reason he pulled out from our business completely.

I was dumbfounded and really left in a lurch. My fiance became angry and accused me of telling my co-founder bad things about him..he couldn't understand why he was so sensitive and left. Regardless, we continued conversations with this other doctor/executive...went to meetings and I (as CEO) ask him to be on my board of directors. He already told me he was considering investing in my company and he said that HIS hospital (where my fiance works) was also "in".

All of a sudden this doctor/executive stopped contacting me. He never signed the legal documents my lawyers drew up for him offering him 3 percent equity (over time) for being on my board...and an opportunity to invest. Instead he suggested he might BUY my company. But he never did.

My initial belief was that my developer (former co-founder) talked with him and told him not to work with us. I just left it alone...but it has been a bitter pill to swallow. This was 3 months ago.

A week ago, my fiance told me that he told his colleague the story about this doctor/hospital executive and how he tried to BUY "our company" but didn't get the right amount and that's why my deal with his hospital went south. He called this executive a "crook" and "opportunist" to the colleague...he was peaking with.

Well, it got back. The doctor texted my fiance and told him that he might get a lawyer for slander...and that he couldn't believe what he heard about himself. My fiance texted him back... and told him that he didn't like the way he was talking about "our business" (IT"S NOT HIS BUSINESS! HE HAS NO EQUITY AND WILL NOT HAVE BECAUSE HE HAS RUINED HIS CHANCES IMO). He went on and on about how the guy was a crook and that he "used us" get free product and never followed through.

So I am in a hot mess. The doctor/executive never contacted me at all. But I am worried that my fiance is acting like he represents my company. Do I need to worry? Also, I'm concerned if I tell my company lawyers...they will have a BIG issue with all of this and worry that we have disclosure issues for the future. Thoughts?