Need some ex relationship advice?

So, my ex girlfriend/girl i was engaged to for 3 years have been split up For 7-8 months now. We both made a lot of mistakes and treated eachother poorly. We was on and off a lot. Well, she contacted me 3 months ago because my mail came to her house. We facetimed for about an hour and i tried taking her to dinner. She was showing me about how she looks now, the improvements she did to her house, refinanced her house to pay her new car off, and bought her son a truck. All of a sudden, her phone dies. So she sent my mail to my post office and included a note that said “sorry my phone died.” We haven’t spoke since. I have blocked her on all social media since we been broke up and have never tried to contact her since we split. In December, my brother told me she has a new man now and showed me pictures of her, him, and the her two kids at the dudes house and them together captioned “love my boys.” I rarely thought about her since we been split until i seen the picture with another guy and the caption she put. The dude was a fat guy and not attractive. It would hurt more if he looked better than me but he don’t and people have told me that. I have been eating clean and hitting the gym 6x a week because i love it and want to become more attractive and better overall and change my old habits and routines to mix things up. I got a new mindset now and realize everything i did wrong. I guess my self esteem went down the viral because of this toxic relationship. Am i the issue look wise or do i need to change my ways internally?

Need some ex relationship advice?
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6 mo
The guy she is with now is the total opposite of me and my identity. He is 300+ pounds, spiked hair, beard and not good looking….
Need some ex relationship advice?
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