Jealousy?

Does anyone else struggle with jealousy in a relationship? I am recently engaged and am getting married soon, but I am trying to overcome this jealousy issue I have been facing. It started about 6-7 months into the relationship. We see each other all the time which is amazing, but then when she spends a few days with her friends I feel like I am not worth it anymore. The trust we have between each other is amazing and I am not worried of losing her, but why is this jealousy controlling me so much? How can I prevent it? I have had jealousy issues in a past relationship, but that was due to the relationship being very toxic and the girl was causing jealousy intentionally. Any tips?

Thanks!

 

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