In this week's Parsha, Yaakov and Yosef are reunited, seeing each other for the first time in some 22 years. The Posuk states that when they first saw each other, Yosef threw himself upon Yaakov's shoulders and cried )בראשית מ"ו:כ"ט(. Observing that the Posuk indicates only that Yosef cried at this time, while saying nothing about what Yaakov did, Rashi here quotes the tradition of Chazal that Yaakov was busy at that moment reciting Kerias Shema, and thus in fact did nothing else at all. There are many questions raised in connection with this idea of Chazal, and many explanations are presented by Meforshim and Darshanim. On a simple level, though, one could suggest that Yaakov merely manifested his jubilation and excitement upon seeing Yosef by expressing some sort of Tefillah, or perhaps an offering of thanks, to Hashem, and therefore did not display his emotions, at least initially, in any visible way.
The Gemara in Berachos (דף נ"ח:) states that upon seeing one's friend after not having seen him for at least thirty days, one must recite the Beracha of שהחיינו, and upon seeing one's friend after not having seen him for at least twelve months, one must recite a Beracha the מחיה המתים. This ruling is qualified by Rabbeinu Yitzchak in Tosafos (שם בד"ה הרואה) who says that it applies only to a dear or beloved friend, and by Rabbeinu Yonah, (שם דף מ"ג: בדפי הרי"ף בד"ה הרואה) who says similarly that it applies only to a friend whom one is very happy to see; the Rosh (שם פרק ט' סימן ט') mentions both of these points. The Shulchan Aruch (אורח חיים סימן רכ"ה סעיף א') rules in accordance with the above; the Mishnah Berurah (שם ס"ק ג') notes that these Berachos are to be recited with שם ומלכות, that is, mentioning ה' א-לקינו and מלך העולם, the full text of a Beracha. He also quotes from the Poskim (שם ס"ק ד') that when מחיה המתים is recited, שהחיינו is not.
The Beis Yosef, in his commentary on the Tur (או"ח שם בד"ה וכתב עוד), quotes a Teshuvah from the Rashba which indicates that there is no difference in these laws between men and women; these Berachos are to be recited by a man or a woman, no matter who is seeing whom, after the requisite length of time. The Shaarei Teshuvah (שם ס"ק א'), however cites those who rule that a man recites these Berachos even upon seeing a woman only if the woman is someone in his family, like his wife, his mother, his daughter, or his sister. He then adds that a woman likewise recites these Berachos on seeing a man only if the man is from her immediate family. The Mishnah Berurah (שם ס"ק א') mentions as well that there is no difference in terms of the requirement to say these Berachos between a man and a woman, but stresses too that a man says them upon seeing a woman only if the woman is from his immediate family. He then elaborates upon this decision in the Shaar Hatziyun (שם אות ב'), explaining that it would otherwise be improper for a man to be seeing a woman altogether, and certainly inappropriate to feel so close to her and so happy to see her so as to be obligated to recite the Berachos in the first place. The same reason would presumably explain why a woman would not recite these Berachos upon seeing a man other than one from her immediate family.
What if one does not see one's close friend for a long time, but regularly receives letters from him or communicates with him somehow (such as, perhaps, on the phone) during that time? Would he still be required to recite the appropriate Beracha when he eventually sees him again? The Be'er Heitev (או"ח שם ס"ק א') quotes a distinction between the two Berachos. If one is separated from a friend for thirty days, he does recite שהחיינו upon seeing him again, despite having recieved mail from him in the interim, while if he is separated for twelve months, he does not recite מחיה מיתים upon seeing him again if he got mail from him during that time. The Shaare Teshuvah cited above quotes this too, adding that perhaps no Beracha is needed even if he never received letters from his friend, but heard from others about him, or got regards from him, and thus knows he's well. If, however, he hears that his friend is sick, whether directly from him or not, and then he sees him healthy again, the Mishnah Berurah quotes in the Shaar Hatziyun (שם אות ג') that he should certainly make the proper Beracha, because he is undoubtedly very happy to see him now.
The Mishnah Berurah (שם ס"ק ב') writes that this question of whether receiving letters makes any difference is a dispute among the Poskim, and he concludes that based on the rule of ספק ברכות להקל, which eliminates saying a Beracha in a case where there is some doubt, no Beracha should be recited upon seeing the friend if he got mail from him. Interestingly, though, the Mishnah Berurah does not distinguish between the Beracha ofשהחיינו and the Beracha of מחיה המתים, eliminating both. Many other Poskim, however, as the Aruch Hashulchan (שם סעיף ב'), the Kaf HaChaim (שם ס"ק ד'), and the Kitzur Shulchan Aruch (חלק א' סימן נ"ט סעיף כ') follow the Be'er Heitev that the Beracha of שהחיינו remains required even if one recieves letters from the friend.
The Aruch HaShulchan (שם סעיף ג') observes that today, people are very lenient regarding these Berachos, not saying them at all in most cases, but he rules that if one really feels great joy upon seeing someone, especially a parent or a child, he should indeed say the proper Beracha. The Kaf HaChaim too (שם ס"ק ו') quotes that nowadays people don't make these Berachos at all; he recommends saying שהחיינו, when required, without the full שם ומלכות, and saying מחיה המתים, when required, in one's mind, without verbalizing it. Alternatively, one may, he suggests, eat a new fruit which requires a שהחיינו at that time, and discharge his responsibility that way.