The authentic ahadeeth are not just the words of
men, rather they are the words of the
Messenger of Allah. If a hadeeth is authentic, then there is no questioning it. Unless ofcourse you are a scholar and you doubt that it is authentic, based on certain evidences. However, if a hadeeth certainly is authentic, then there is no questioning it. Because it is the words of the one whom Allah sent to convey the message of Islam. Allah says,
Say: "If ye do love Allah, Follow me: Allah will love you and forgive you your sins: For Allah is Oft-Forgiving, Most Merciful."
[3:31]
Therefore, Allah's Love is earnt through following the Messenger. But as for you having trouble with the issue of apostacy, then there's not much I can do for you there. The ahadeeth about that are authentic, therefore it is a part of Islam. In fact, the following hadeeth is recorded in Bukhari (3017);
"Whoever changes his religion, kill him." The apostate is first asked to repent by a Qadhi in an Islamic country, and if he refuses then he is executed. Maybe this will help clarify:
http://islamqa.com/index.php?ref=696&ln=eng&txt
http://islamqa.com/index.php?ref=811&ln=eng&txt
http://islamqa.com/index.php?ref=20327&ln=eng&txt
http://islamqa.com/index.php?ref=14231&ln=eng&txt
Just because someone is punished in this world, it does not mean they will not be punished in the Hereafter. An apostate has left the realm of Islam, therefore he/she will inevitably spend enternity in Hell. But we have also been told through the Sunnah that the punishment of the apostate is death in this world. So we hear and we obey, there's simply nothing else to it.
About your question on context. I'm not sure, but I will ask someone more knowledgeable for you inshaAllah.
The ahadeeth about women taking a mahrem when travelling are not specified to a certain time, therefore they apply at all times. This is the opinion that I follow, and this is what I have read/heard from the majority of scholars and students of knowledge whose books/lectures/fataawa I have come across. The Prophet salAllahu 'alayhi wa sallam said, “It is not lawful for a woman that believes in Allaah and the Last Day to travel the distance of a day unless accompanied by a
mahram.” And that is what we should follow. The key word here being
mahrem. A group of women cannot serve as a mahrem. As shaykh Fawzan states:
Also see
here. The shaykh further states:
So even though Hajj is one of the pillars of Islam, the woman is not permitted to make Hajj until she has a mahram, and she is excused until she does. See
here,
here and
here. So what about travelling for matters which are not obligatory, or even recommended? Allah knows best. You can also visit the following links about the mahrem issue:
http://islamqa.com/index.php?ref=316&ln=eng&txt
http://islamqa.com/index.php?ref=102494&ln=eng
http://islamqa.com/index.php?ref=22369&ln=eng
Allah knows best. May He forgive me for saying anything incorrect.