One of the hardest things about grieving a rejection is that you don’t get the same kind of support in your grief that those who lose mates to death get. People do just do expect you to suck it up and move on. To get over any loss you need to be allowed to grieve over it as you do your best move forward as best you can. Expect to move slower, have less energy, and maybe feel a bit crazy and forgetful.
Grieving people need to eat right, get enough sleep, and maybe even journal. It does more good than just hopping into bed with a new person or finding another means of escape. Escape doesn’t heal grief, it just delays healing. Grief demands you work it through. If you don’t, it will pop up and hit you when you least expect it.