You’ve got several different issues going on here, so I’ll try to call them as I see them:
- The issue of having a friend who identifies themselves as “gay”: No, the Church does not teach any sort of shunning of individuals regardless of their sin. HOWEVER, we should in no way encourage or approve of their sin. So, if you have a friend who is “gay” you must be clear about that. Talking about their latest “boyfriend”, for example, would be problematic-- unless you are sharing the Gospel and encouraging them to discontinue their lifestyle. Also, invitations to your home or events might be a problem as you could not acknowledge any “partner” in such an invitation.
And, you must also be cognizant of how your willingness to engage in “girlfriend” talk with this man also contributes to his identification as “gay”. Personally, I think it’s on the line there-- by talking to him in this “gay” manner you are encouraging him and tacitly approving of his lifestyle. The fact is he is NOT a girlfriend.