How to stop feeling upset/jealous when my boyfriend goes out?

Let me start with saying I’m already fully aware this isn’t a healthy mindset to have as I do trust him but it’s very easy for me to feel left out especially in this instance when I’m sick and at home how can I stop obsessing over the fact he’s out having fun while I’m sitting here alone?
How to stop feeling upset/jealous when my boyfriend goes out?
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