I have a few things. The first one is the mirror. I look to see the faults can fix. The 2nd I knowing in a year I will be moving from a small trombone to a 20-j (massive tuba for those who don't know) for college to I need the muscles. And if all that doesn't work ANW ( American Ninja Warrior on G4) I want to be able to try when i get to entree age. So those things motivate to keep training.
How is your diet? I was in your situation. After I had my son I was losing weight but didn't see it. Not till I stopped eating a lot of processed food... One week of eating only veggies fruit eggs, low-fat milk did I start seeing drastic results! In one week I dropped 5lbs!!! Seeing my body mold and conform to how I mold it, that keeps me going! Also what kind of cardio do you do? Try to find something fun like Kickboxing or Power Yoga, just like your diet, your workout routine should be well rounded! Keep Moving Forward
I get the sane way at times. I just keep reminding myself what all the good results down the road for my hard work. Cheer up and move foward.
Visualize picturize believe it and receive it, see your self there, know your steps to get there, keep those who believe with you, know you throw your heart into it believe it, your already there before you even there..
Fear of failure motivates me, visualise what you want and go out and get it. Prove any doubters wrong, the onky barrier to your success is your mind, push your mind and the body will follow. You look great already by the way.
Something that motivates me is music. Find tracks that'll get you pumped up. My bro definitely pushes me when we workout together. Got to have a good workout partner.