Q. Aren't some things about us harder to change than others? For example, I just have a very hard time being patient.
Yes, some things about us usually are harder to change than others – but that shouldn't keep us from trying (with God's help).
I have a friend who says (with a twinkle in his eye) that his favorite prayer is this: “Lord, give me patience – and give it to me right now!” Patience, he admits, has been the hardest virtue for him to acquire, and I suspect that's true for many of us. Our patience is tested every day – even every hour (unlike some of the other virtues). It's also the key to other virtues God wants us to have. You'll never be compassionate if you lack patience.
When impatience threatens to overwhelm you, ask God to replace it with his patience. His patience with you has been beyond measure. In addition, learn to ask yourself what your impatience is actually accomplishing.
Also ask God to help you care about the needs of others more than your own. Don't lose patience with them; instead, pray for them.