One possible antidote to FOMO and weekends of wondering may be experimenting with different hobbies and personal pursuits apart from your career interests.
Many hobbies and pastimes exercise a conscious and deliberate focus relegating other ideas to "the back burner."
Spending time in nature can be very self-nurturing, and may sometimes be paired with exploring photography, sketching/drawing, plein air painting, and/or journaling or logging steps taken, venues visited. Cooking is another activity in which a keen interest may be developed, and this can be related to gardening (growing fresh herbs, spices, produce such as vegetables or fruits). Decorating, landscaping, woodworking, sewing, knitting, crochet, singing and/or playing music are other creative endeavors which can be dabbled in and/or developed over a lifetime. Collecting can also be absorbing... just be sure that your collections will fit in the space you have available. I'm familiar with collections of rocks, shells, vintage baseball cards, miniature books, stamps, coins, and items featuring specific pet breeds.
As a millennial who may have been steeped in an era of educational approaches which may have emphasized collectivism
, hobbies and pastimes can encourage reflecting on who you uniquely are, and aid in exercising your personal decision-making, leadership, independence or inter-dependence in a low-stakes arena (away from one's career). This can be a strong antidote to focusing on what others may be doing that you may be missing out on, essentially being a follower.