I lived with a couple in an apartment for 2 years. They have four kids and I am like a member of it. The wife went for a 2 weeks vacation and when she got back, the hysband was claiming that I had a relationship with him. Or just a sexual act happened between us. The wife believed and it has spread to our group. The wife have made up proofs including a fortune teller that I am the culprit of his husband's wanting to leave them. My conscience is clean and clear. I don't know how to defend myself.

You can't prove nothing happened... proving a negative is impossible. All you can do is proclaim your innocence of this, I assume you no longer live with them. If you do... its time to leave.

The gossip fired while I am overseas and now I have to go back prematurely to see what I can do. I pity the kids. Please give me more tips. Thanks

Merely ignore or deny it, nothing else you can do.

There really isn't much you can do... the woman is having delusional episodes obviously... and as a non-family member there really is nothing you can do. Personal;ly, as I said before... for a non-blood relative acting like this? Put a lot of distance between them and yourself. Lifes too short to waste any of it dealing with lunatics. As you said... YOU have a clear concience because nothing happened. And at the end of the day... thats what matters most.