I miss my ex-boyfriend so much

You can do anything you want to do.

However, you're clearly not ready to start dating again. Take this time to work on yourself. Refocus energy on education or better job prospects. Learn about your industry and seek out promotion opportunities. If none are available where you currently are, consider a job transfer or change jobs.

Look for ways to improve your life. Helping others is always a good thing. Volunteering is needed almost everywhere. Whether it's at a nursing home or school or animal shelter, the experience allows you to interact with all kinds of people.

Don't consider one bad experience to be the norm in your life. Chalk it up to bad timing and move on to bigger, better things and people. When you're ready to date again, it will be much nicer and easier. Until then, get moving.

Remember who you really are, unique as a centre of conscious awareness in the heart of the Absolute which is the source of all things.
The sun shines from which all energies derive in the solar system.
Face it and ask for the strength to put aside the experience and not be miserable over the loss of an insensitive betrayer of your affections. Forgive and carry on. I have found this helpful.

Something holds you to him. Define it. ( humor, looks, sex,) or maybe you are still in love with being in love.

Anyway ... he hurt you and is gone AND he is your past.

So find these “enduring qualities” that make you stuck in someone else, like a guy who is true and faithful.