..is love (or loving a person).
It’s hard to move on from someone who you’re so familiar/comfortable with and used to. Even in toxic relationship. Actually, especially in toxic relations.. since psychologically you know it’s toxic but you keep wanting it more.
But like all things, if you can get addicted, you can also cure yourself. Time will heal everything. Most probably don’t know/realize this, but humans are generally toxic. You’re probably better/happier by yourself. Don’t be afraid of being alone or being lonely. It’s a blessing in disguise.