Rebekah was the girl who watered the camels for Abraham's servant and through her obedience was chosen by God to marry Isaac. She left her family very quickly and went with a stranger to marry a stranger. Rebekah wasn't able to have children for 20 years after she was married, and only through a miracle did she conceive twins, Esau and Jacob. She played favorites with her children and caused her blind husband to pass on the eldest twin Esau's blessing to the younger twin Jacob.
We can learn a lot about her from looking at her whole story. She had an impulsive behavior that had major impact on her life. On one hand, her courage and boldness allowed her the opportunity to marry into a wonderful lineage. On the other hand, she was so head-strong that she decided that her favorite son deserved the blessing intended for the other.
Now it is true that Esau had married two "pagan" women, which the Bible says was a great disappointment to Isaac and Rebekah. Esau also gave up his birthright because he wanted some of Jacob's cooking (and traded Jacob for it). But for Rebekah to move outside of God's ordered plan gave God quite a few messes to clean up.
What I got out of this story is that just because we may have been good at following God's will, doesn't mean that it will get easier as we go through life. Rebekah's ability to wait on God for her perfect husband worked out well for her (my Bible commentary says she was probably older -atypical for that time). But her lack of trust in God for her son's future caused many problems. Let's take all of her story and make it part of ours so we can learn from her blessings and mistakes.