With the end of the Three Weeks, weddings resume, attending places of entertainment is again permissible, 
The thought of being in the King's presence should similarly elevate our day and our deeds.
playing music is allowed, and it seems that everything is back to normal. We get that feeling several times a year - after Pesach, when we pick up the "rest of the year" regime in the kitchen; after the sefirah, when the period of semi-mourning concludes; after the Tishrei festivals, when we come down to reality and most synagogues become rather empty again. In a sense, the same thing applies three times a day during davening, when we take three steps back at the end of the Amidah.
In all of those situations, it is useful to bear in mind the words of the Talmud in relation to the Amidah. What the sages say is that the three steps back are like taking leave from a king (Yoma 53b). The implication is that there comes a moment when the audience with the monarch is over. One has to leave the throne room, walk through the palace to the front door and emerge onto the street.
At that moment life is back to normal. But the memory inevitably lingers. It colours one's thoughts and feelings for hours, even for days, months and years. After the Amidah, the thought of being in the King's presence should similarly elevate our day and our deeds. After every highlight of the calendar, we should also find ourselves invigorated and inspired.
As far as the Three Weeks are concerned, the message that lingers should be one of greater devotion to the Jewish past and destiny.
The Right Dosage
The rule is clear: "Do not add to the word which I command you and do not subtract from it." (Deuteronomy 4:2) The rabbinic comment is that you should not place five passages in the tefillin instead of four, take five kinds of plant on Sukkot instead of four, or have only three items where four are commanded (Rashi).
There are complaints these days that some people make Judaism harder by introducing new stringencies - as it were, acting as if Judaism did not have enough rules already. True some Jews are becoming stricter, not out of 
If the doctor prescribes medication, do we change the number of doses?
masochism or intolerance, but because of love of God. They cherish the commandments so much that where there is a stricter as well as a more lenient option, they prefer the stricter. This is only a problem if it makes people boast of their piety and denigrate those who think differently.
The real problem is with those who subtract from the Torah - not seven days of shiv'a but one; not two days of yom-tov but one; not 24 hours of Shabbat, but only Friday evening; not the whole benching, but the short form or none at all; not a full agenda of Jewish living, but an abridged version that may diminish further.
If the doctor prescribes medication, do we change the number of doses or the strength of the medicine? Since God, the Heavenly physician, has worked out a balanced diet and the correct dosage for spiritual health, why should we think we know better?