Does uttering "I have divorced her and she is unlawful to me" constitute a divorce in a state of extreme anger and without the intention of divorce, especially if the speaker does not remember saying it?

Your statement to your wife's uncle: "If she does not come by ten o'clock, I will divorce her," is merely a promise of divorce, and nothing takes effect thereby. As for your statement to your son: "Take your mother, for I have divorced her and she is unlawful for me," this is an explicit divorce, and the divorce takes effect if you said it consciously. You may revoke it before her waiting period (iddah) expires, if it was the first or second divorce. The phrase "she is unlawful for me" carries several interpretations, and if you do not recall your intention behind it, then an expiation (kaffarah) is binding upon you according to the Shafi'i school. It is advisable to consult scholars to determine the specific ruling.