Starting Over!!!

Hello all! I'm very new to this site. I am 20 years old and basically starting over. About 2years ago, I was at my highest weight 196lbs and I did Weight watchers to lose about 30lbs. However, I couldn't afford it anymore so I started just working out and following what I had learned. I lost about another 5-10lbs, and plateaued. Life was good for me at that time and I focused on myself. Then I started a new job, where I worked 10-12hour shifts and rarely had time for myself. I was engaged and had bills to pay so what little time I had I wanted to spend with my fiance at the time. Then things started going downhill. I slowly start to gain a bit of weight, lost a lot of muscle. Then my fiance lost his job twice in a 5 month period, leaving me to pay everything on my own. I held on though, until I got struck with the stomach flu. The job I had, did not tolerate absence and I was shortly let go. With neither of us having a job, I couldn't afford my rent. A family member kindly offered me and my fiance their home to stay and get our lives back in order. We accepted. Needless to say, I was stressed. I stopped caring and just wanted to get out of the hole that I was in. We moved into the house and stayed together for another month. My fiance then said that he realized that he just "wasn't ready to settle down." He went back home to his mommas, and I stayed with family. I found out a couple weeks later, that he went back to be with the girl he had cheated on me with. It was a low and very painful point for me. I ate a lot or wouldn't eat at all. I've been having an internal battle with myself, on what I deserve and who I want to be. And that has pushed me to focus on myself again. I want to start over and be the person I use to be. Confident and healthy. I think I know how to do it, I just need reminders so if anyone has advice for me or useful tips, please feel free to leave a comment. Much appreciated!