How do I gain motivation and self worth?

I have a problem not fully applying myself. I have low self esteem after how my father and brother have treated me for 16 years. I want to improve myself by being happier, exercising, doing activities and work for the job I want in the future I find it so difficult to have motivation because I keep on thinking to past interactions with them. I often wonder “what if they’re right, what’s the point?” I was treated like garbage and I am only furthering their points that I am what they told me by NOT improving myself and it’s such a destructive cycle but I don’t know how to break out of it. It’s so hard for me to find happiness in things I enjoy because I keep telling myself I’m not good enough. I feel so unmotivated on some days and I don’t want to be this way! I want to have the body I envision in my head, I want to be able to work towards my career without thinking the work and effort I put in is hopeless because I’m not good enough yet. I keep telling myself “We are going to change” and I try but I keep on falling back into my regular cycle and I’m sick of it. I can’t seem to pull myself away from these bad behaviors and I just want to find something, someway, to help me get my life actually started and I can be free from the memories that keep on surfacing throughout my every day. Thank you for reading it means a lot.
Asked by Lemon

Hi. You can talk back to your thoughts. You can even name it if you would like. You can call it a name like Bobby or something like "the worry monster." When you ask yourself "what if they're right?" reply with "What if they're wrong?" A couple ways to increase your self-esteem is to state a positive affirmation many times a day and also to say or list 3 of your qualities daily. State, "I am enough" repeatedly as you shower. Write "I am enough" on every mirror you own. Listen to an "I am enough meditation." You can find this on YouTube. I recommend one by Marisa Peer. However, if you don't like that one, choose one of your liking. Write "I am enough" on your hand. Set a reminder in your phone that goes off twice a day that says, "I am enough." 

Think of 3 of your qualities daily. Write them down in a journal or look yourself in the mirror and say 3 kind things to yourself. Tell yourself the things you would have wanted to hear from your dad or brother, a boss, friend, anyone. Say things like "You're amazing!" "You're kind." "You're successful", etc. Listen to 3 Secrets to Boost Your Self-esteem by Marisa Peer on YouTube. Also listen to Why All Our Insecurities Come From This One Thing by Marisa Peer. 

Think of 3 things you did right today. What does that say about you? If you listened to a co-worker, it could mean you're a good listener. If you finished a project, it could mean you're diligent. Another way to think of your qualities is to think of qualities you don't like in others such as lying. If you don't lie then you can say, "I am honest." Or what positive things do others say about you? Write it down. 

We are operating from our subconscious 95% of the time. Your subconscious doesn't differentiate from fact and fiction. It will believe whatever is repeated enough. You only believe your dad and brother because you heard it 16 years. It wasn't true. You can reprogram your mind by telling it new affirmations like "I am enough" and reminding your subconscious of your positive qualities over and over again---every single day. Consistency is key. 

It's great that you're exercising. Other things that build happiness are practicing gratitude (look up the scientific benefits of gratitude), meditating, positive journaling, acts of kindness, and fostering social relationships.