I'm selling my horse as I've outgrown him and won't be getting another one til spring (four months). Owning a horse has been my life for 5 years and I don't know what to do now.

You could ask or find a horse that you could loan or ask people on your yard/barn if they need there horse excercising or ridding and looking after X
Ride other horses if you can ! This period will be a good opportunity for you to improve your riding skills, and by doing so you will be ready to adapt to the new horse :)
Focus on the great times you'll have ahead with your new lucky horse and don't lose heart! Also think of the money you'll save in those 4 months
Time will fly by
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