The only way to deal with jealousy is to yield to it and work with it, have some fun with it, use it to mind f*ck your women. Don't *try* to fight and conquer jealousy it just won't work and will simply amplify your problems. Embrace jealousy and look at it objectively and you'll soon realize that it has no power over you.
For example, your chick is hanging out with some male friends and it bothers you deep inside? Well, you simply tell her something as follows: "Hey Sandy, are you going to hang out with Robert tonight?" She'll say "yes I think so". You say "great. I hope you have some fun. You know that Robert is really smart and sexy. Sometimes I think you and him would make a better couple than we do. I mean you guys have all the same interests, you never argue, and you even dress alike (here you're subtly putting down the guy or her...or whoever dresses like crap...) Sandy, if ever we decide to start seeing other people, I'd really want you to hook up with Robert"....This will make her all insecure and jealous about you. She'll say things like "Lefty, what do you mean if ever we start seeing other people? And by the way, me and Robert fight all the time and I think he's so unattractive really. I think of him as a brother...Do you want to see other people? Is that why you're mentioning me and Robert?".... It may seem simple but it works like a charm. Now you've made her jealous and insecure about you, when she's the one hanging out with the other guys.
What I do with my LTR chick just for fun is the following:
She's an artist while I'm a finance dude in a suit and tie. So we already look incongruent together.
So every once in a while we're walking downtown and some bum on the street with tatoos and rags walks by begging for money, he looks like the artsy type of guy with all kinds of piercings and stuff and I'll say "hey babe, check out this guy, he must be a musician or a painter, just like you. Maybe you should date him and simply have an affair with me"...hahahaha....
She goes nuts every time I pull this trick. She'll get all insecure and think that I want to fool around on her....or that I see that we're not compatible in the long run. She'll say me and her are like "Dharma and Greg" from that stupid sitcome...
Other times, I'll deliberately start an argument about something where I know she'll have strong feelings for and then I'll use that as a launching pad for more fun and games.
For example, the other day she was talking about how the Vatican is against gay priests. So I'll say "the Vatican should never f*cking allow gay priests in their ranks. Gay priest are perverted sick animals"... LOL...and then she'll get all riled up and comes up with a million rational arguments that just blow away my irrational nonsense....
and then I'll say "you know what, lets just agree to disagree ok sweetheat. The bottom line is that I'm a conservative finance guy and you're a liberated artist; we're two totally different people. If you want a guy to agree with you, you should date that musician/painter we saw on the street today begging for money"....hahahahaha... "Baby, some artsy fartsy guy will agree with everything you say and you'll live happily every after".
And then she'll get all worried that I don't see a future with her....
So to answer your question, by doing stuff like this, I'm never jealous of this chick because I'm litterally throwing the guys at her while she's always qualifying herself to me....
BTW: One last thing, whenever I sarge a new chick who tells me she has a boyfriend, I'll say "oh that's great tell me about him" and she'll tell me a bunch of crap, and I'll say "he sounds wonderful I'm sure you two will get married" and she'll start with stuff like "we'll we're not that serious, we're just seing each other, it's only been a few weeks" blah blah blah. Chicks never wan't to agree about anything. So while I'm pushing them onto the boyfriend, they are actually throwing him off....
BTW#2: Why are you even jealous of a chick dude? You should be gaming the hell out of them.
Cheers,
Cesare Cardinali