Trying to rid yourself of feelings is like trying to stop the wind. My question to you is why would you want to take away your feelings? They are telling you something very important: that you are trying to turn yourself into an emotional pretzel, trying to fool yourself into believing that you can'be cool' with this type of relationship, when clearly you can't.
You yourself said that you feel sick to your stomach when you picture him kissing another woman! You aren't supposed to place yourself in a situation that makes you sick! We need to find out why you are doing just that. You need to be putting your energy in a totally different direction; not on trying to get rid of your feelings but rather on understanding why you want to be with a man who isn't able to commit to you.
Being with him is like trying to get blood from a stone. He's the stone and you keep crying because you can't get what you want out of him. He is a confirmed bachelor, doesn't want commitment--for whatever reason--and you must either take him as he--which you can't do--or move on. Of course, you can always stay and hope that he changes and cry your eyes out each time you have proof that he hasn't changed.
If this is the option that you choose, then you can be sure that you are sticking with him because of unfinished childhood business. We humans fall madly in love with people who remind us of our parent or parents. Our parents were our first loves, after all, and we are drawn to a lover who feels familiar. If your parent was unavailable and made you yearn for more than he/she could give, you would be primed to go after a guy who wants an open relationship.
There is more. You will be drawn to someone like your parent, not just because you are used to this type of relationship, but also because you are hoping that the situation will work out differently this time. You are hoping that this time around, the unavailable lover will want you and only you. And if this ending occurs, the wound you suffered as a kid, and all the pain, the yearning, the hurt, and the anger will be magically healed.
The problem is that this happy ending never happens since we choose lovers and spouses who can't give us any more or any better than our parents did. But hope springs eternal, and we dream that this time it will be different. So we hang in, never break up or divorce, we try to be better, more giving and more loving, hoping that we will finally be rewarded with our happy ending. Despite all our efforts and hope, the happy ending never seems to come.
Each time you cry over this man, you are really crying over the disapppointment that once again you didn't get your happy ending. He didn't choose you to make you his number one girl. You need to see that he never will choose you because he appears too damaged to choose one person. Now the ball is in your court. You can accept him and the crumbs he gives--this is what you were hoping to accomplish if you could only escape your jealousy.
The only way you aren't going to feel jealous is if you are dead or totally brain injured! Not a healthy goal for you and certainly not one that can be accomplished given the fact that you really do want a committed relationship. Your other choices are to keep banging your head on the wall and grieving, or last but not least, give him up.