I think perhaps you are taking your last breakup or relationship issues personally. Maybe you think that it was your fault that your gf broke up with you. Anyway, jealousy often stems from an insecurity of losing someone. You have to allow yourself to think, it's ok that things don't work out sometimes. It's no one's fault, sometimes people do bad things. If someone cheats on you, for example, they did you a favor because now you know they were no good for you. Turn something negative into something positive, like a learning experience.
How about some more details on why you think you get jealous?
I have a long time interest in psychology, specializing in relationship dynamics for 30 years.
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