Lureen was totally business, LD had died, she ran the business. She would have totally looked at it in business stand point, how would've looked if it got out her husband, was having an affair with a man? What would that say about her judgement, 'Well, you husband's queer and you didn't know it? " Oh, yeah she would have quietly divorced Jack, maybe a financial settlement, "let it be".
As far as Randall and La Shawn, just being in the room with LaShawn for five minutes, some folks would think she drove him into the arms of a man. Sorry, but believe that's how some people think.
The scenarios I've come up with may not popular but you have to look at this way, back in those days and maybe even now, some sectors of society would have looked at it no other way.