Why was Esav so angry at yaakov for stealing the bracha even though it was over 20 years since he saw him?
He felt like the bracha totally determined his destiny and that of his offspring forever.
If you look at what Yaakov sent him -- a specific number of male and female animals. 200 female sheep + 20 male sheep could be: 220 sheep that you use up, or a breeding supply that you can use to produce lots more. What you make of it is up to you.
Esav felt like "that's it I lost the bracha my life is ruined and it's all Yaakov's fault"; Yaakov is replying "you're still in control of your life, and it's up to you to decide what to make of it."
Because the eyes make the heart fonder. For 20 years Esav only remembered that he had been cheated by his brother. At seeing him after all those years, his mind had been given the chance to go through all the good time they had spent together. His brotherly love was back again.