Quarter life crisis

M
I'm about to graduate from college and I'm freaking out. The plan is to go on to grad school to get my license as a speech-language pathologist, but programs are so competitive that I might not get in and I'll have to reapply next year. I still live at home but will likely be moving out for the first time after graduation (a little late, I know) and I'm really sad to leave my family and our dog who may not live much longer. I also feel so strange lately and have been having anxiety at night thinking about how I have no idea what's going to happen. I've also been thinking about death a lot because of all the terrorist attacks, my friend's dad's passing, and the illness of my mom and our dog's old age. Thinking about death has made me have anxiety in the middle of the night when I think about how no one can escape it and myself and everyone I love won't exist one day.  I'm completely single, me ex has a new girlfriend, and I feel really lonely, especially now that it's the holidays. Basically I'm just freaking out about every aspect of my life. Is there anyway I can get back to my old, fun-loving self?