I literally just left a toxic relationship with a narcissist.

I feel completely unsupported by my family. and I feel like I miss him even though he put me through so much abuse.
YES, I am in therapy.
YES, I am codependent.
YES, I have been tolerating this abusive behavior for 4 years
and YES, We have a 2 year old together.

I am in my own apartment now just now starting my life over again. I have no friends. I have no support system. and I know my son misses his dad.
Apart of me, just wants to walk away from even trying to be independent and just allow myself to be dependent on a man.
I know it sounds stupid but it is honestly all I know.
I am 23 years old. and I really feel like the weakest person ever and I feel like a terrible mother for leaving my abusive partner because our son loves his dad soo so so so sooo much!

I am codependent so my therapist suggested I cut off all dating for a year and try to do it on my own.
THIS IS THE FIRST TIME I HAVE EVER BEEN SINGLE. LIKE EVER.

I normally would just contact an ex if something happened and move on from the pain I was feeling but now, I am forced to focus on staying single and not going back to relying on a man.
I don't know why I am struggling with it so much. Why do I feel like I need a man? Why can't I be happy by myself?

I was so desperate to be have that fairy tale love, that I literally stayed in an abusive relationship because I was to scared and weak to leave, but also because I waskind of used to the abuse and apart of me liked not having to make the tough decisions. I liked the security of being taken care of.
But- It got to a point, that I could not stay any longer because my life, health was in jeopardy.
He had started having unprotected sex with prostitutes along with the emotional, financial, sometimes physical abuse.

I guess, my question is, how do I make this easier for myself?
When I am feeling this depressed and alone in my apartment how do I convince myself to not go back to him?