Yeah, it is. My kids both left for college/career 5 months after my Dad died. It seemed like I lost 3 people that year.
BUT, the good news is, my kids are grown and have come back. My 26yr old son lives here in the same city now and I see him often and my daughter is a recording artist in NYC, but I talk with her all the time and see her atleast twice a year.
Hard as it is, we've gotta let go in love and faith that they'll be watched over and kept safe while we're apart and that they'll learn when they fall and have to get back up again.
Hang in there. You're doing well.