Don't let him get you down! The fact that you even want to take classes is great! One class, or a full courseload - so long as you're out there and doing it! It doesn't matter if it takes you ten years to do it!
You yourself said that your happy with how your life is right now, so why doubt yourself simply because your not doing what your dad wants? My grandmom was the same way - I was never thin enough, fashionable enough, never dated the right guy, etc. then when I went against what she thought I should do? Boy, heck broke loose. I didn't talk to her for years after that. Now I'm married and have a husband who's completely great and supporting me through a MAJOR life change - I'm starting my own business. Its been my life's dream to work for myself and with his encouragement, I'm actually doing it! We're not making ends meet the way we used to, but we knew that would happen.
I'm telling you this because you need to see that there are two sides to the coin: people who force you to do something you're not and people who encourage you to do something you are. You'll meet both types in life. The easy part is enjoying being with someone who has all the faith in you, the hard part is ignoring the one who poisons you.
All that matters in this world is that you remain true to yourself and that you do what makes you happy.
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