Anger is the most difficult sin for me to avoid. I will tell you some things that have helped me, but I have yet to overcome this sin. I think everyone has one sin that is particularly difficult for them to avoid, some have more than one.
I'm sure your parents are not pleased that you've become Catholic, unless they're very unusual Baptists. If you imagine yourself as a parent sending your Catholic son or daughter off to college and having him or her return home as a Mormon, that might help you understand their feelings and make it easier to bear whatever discord there is between you.
You don't have to let them lay guilt trips on you, though, if that is what they are trying to do. The same goes for your Baptist friends. As for Nietzsche, do the reading and try to be as objective as you can, just analyze what he's saying, understand his arguments. Your professor wants you to learn about an important philosopher but does not expect you to accept what Nietzsche says. It would be helpful to read this article "The Psychology of Atheism"http://www.leaderu.com/truth/1truth12.html
You'll learn a lot about Nietzsche, Freud, and other well-known atheists and have an answer for those who stereotype people who are religious as "dumb." I can't remember if I got that link here or not but it's really a helpful article for Catholics
and other believers who have to deal with atheists and their insults.
More ideas for overcoming anger:
We're supposed to pray for our enemies and anyone who angers us. If you do that, it helps, though not immediately. Keep praying for better relationships with anyone you're angry with, and pray for their souls. There are (or will be) some people in your life you will never have a good relationship with, but you can still pray for their souls.
Anger makes you suffer so offer your suffering up in union with Christ's salvific suffering, for the poor souls in Purgatory.
Ask Jesus and Mary and all the saints to help you get rid of your anger.
Confess your anger and receive absolution. When you do your penance, pray for the grace to resist anger.
I just had EWTN on to see the news report from Rome and saw Mother Angelica saying:
"It's an insult to God when you think your sins are greater than His Mercy."
I think that's quite appropriate to your situation, and probably most of our situations. And don't forget that Jesus got angry!