why would OJ kill wife out of jealousy when he already knew she slept.

 You're such an imbecile!

Well, most people are idiots with bad taste...so there!

Because he got jealous.

Nicole let Ron drive OJ's Ferrari. That alone was worth Nicole getting her dome lopped off and Ron turned into a pin cushion

I'd kill em too. I'm Just kidding of course.

In Oj's book If I did it he mentions he thought Nicole was using drugs. Then he mentions Ron showing up with a envelop so he just assumed Ron was carrying drugs and when Nicole fell.( I believed he pushed her down) Ron went to her defense attack mood Oj called it-karate thing something like that. Oj said he was so Fu...ing mad he would of laughed in Ron's face.. Something like that.

She had affairs during marriage as folks testified why would he go ballistic after divorce?

I think because this time Nicole told OJ that it was over for good. Even after their divorce, they had tried to reconcile, but right before the murders, Nicole had broken off their relationship once and for all. I've read a lot of books on this case, and each book gives some information that the others don't. What I can gather and piece together is that Nicole put a stop to their reconciliation in May. She gave OJ back some jewelry he had given her for her birthday and Mother's Day. She was also going to be moving to Malibu very soon, but that was because OJ had threatened to turn her into the IRS for tax fraud because she was still using Rockingham as her address and saying that the Bundy condo was a rental property. So she was going to rent out her condo and then use that money to rent a house in Malibu. She would be far away from OJ and he wouldn't be able to check up on her and spy on her like he had been doing. He was also going out of town that night, so in his mind, he had the "perfect" alibi. I think he went over there with the purpose of murdering Nicole and did not expect Ron to be there. If not for Ron, there would not have been as much evidence in this case. Although, OJ being her ex-spouse, I'm sure he still would have been a person of interest at the least. OJ murdered her because he couldn't have her any longer, and if he couldn't have her, then nobody could, IMO.

I think it was because of Marcus Allen doing her. He told her see him again and I'll kill you, and she apparently didn't listen.

They were both well known swingers. O.J. had no problems with her messing around when they were married. Never mind that it was documented that after their divorce Nicole written O.J. a letter begging to get back together. The jealousy motive never made much sense under scrutiny.