Missed miscarriage- cant stop thinking about about what went wrong

No heartbeat was found in the ultrasound.. based on size it appears the baby stopped growing at 6 weeks when i should have been 9.5 weeks pregnant.. i have to wait for 2 weeks for a second ultrasound or to see if i bleed out.. its not been called a missed miscarriage yet by the doctor but i have been told not to be too hopeful either.. I feel so upset.. why did this happen to me.. i took such good care.. i made lifestyle changes, i ate healthy, i took prenatals 6 months prior.. i did everything by the book.. people around me are having babies left right and centre.. some without even trying.. some drinking well into the first trimester.. i know this sounds petty, but i just cant stop thinking about it.. i feel weepy randomly at work.. i dont feel like meeting anyone coz they all talk about thier kids.. anyone who experienced this how long did it take for u to fully heal?#adviceplease