Close male friends do hold hands and do kiss each other on the cheeks. It is also normal for good friends to keep holding on to the others hand after the initial handshake. This is a sign of trust and affection and not homosexuality. I have a few Arab friends here and although it is initially a little strange it is also good when this happens as it is a sign of acceptance.

The adultery thing is a different issue altogether. I agree it is a very uncomfortable and strange thing for us but it is completely separate from how males relate to each other.