How can i get over this?!

How can i get over this?

The exact life that i wanted The exact life that I wanted I could have had, if I had of hooked up with the guy in London rather than stayed with an idiot, and stayed in the job I loved, rather than coming home, all I can think about is that, and I have missed the opportunity and lost the awesome girl I used to be, everyone said it was because of depression but I I knew in my heart I had to go back and for some reason listed to everyone else, and didn’t, now I have compltelty screwed my life and cannot see anything making me happy, thereis nothing that I want to do…….i did have so many plans for myself but now no matter where i am i think about what i could be doing had i of been smarter, there is nothing i can do to chagne the last 6 months and there is nothing that i really want to do, and i'm so ashamed of myself, how can i getback to the girl i used ot be and stop thinking lik ethis?

2 weeks ago
I have already been seeing a counsellor and taking meds for months but neither of htem are helping, as i am just ruly unhappy with my current life

A few sentences here won't bring her back. You have to do it yourself with the help of your family, friends, therapist, or medication.
You can never look back and think about what might have been. If you stayed things may not have turned out as your expected, things rarely do. All of us have been there, wishing we had made different choices in life but you can't go back only forward.
You really need to talk with someone and soon before this depression gets much worse.