I heard these ideas from Rabbi Yechezkel Freundlich:
Rabbi Yaakov Emden (I think that's who he quoted) wrote about the idea of why this particular galus that we are currently enduring has lasted for so long - nearly 2000 years. While many have attributed this to our people continually being mired in the sins that caused the destruction of the Beis Hamikdash - namely Sinas Chinam, lack of proper respect, failing to say the brachos before we learn Torah - Rabbi Emden said that there is a different reason why we have caused the exile to endure for such a lengthy period of time.
We don't mourn properly for that which we have lost.
To a degree, this seems to be understandable, since none of us ever experienced the Beis Hamikdash when it existed, and therefore it is hard for us to find personal meaning in connecting to the mourning practices that we observe during the 3 Weeks and on Tisha B'Av itself.
Rabbi Freundlich offered two ideas that could be very helpful in making these forthcoming 3 weeks productive in preparing for Tisha B'av - if the Moshiach should not arrive before then (which I hope he does).
1) Often, most people don't open the Kinnos until the night of Tisha B'Av and thus have very little familiarity with it - on top of the fact that we all get exhausted several hours into the morning reading of Kinnos. Rabbi Freundlich suggested that everyone take 5 minutes a day during these 3 weeks to read a Kinnah, understanding the English available to us - and thus utilize these tools that our sages have given us over the centuries to connect to a proper sense of mourning and understanding of our loss.
2) Quite a few of our 19 brachos in Shemonah Esrei discuss our yearning for Hashem's salvation, the ultimate redemption, the arrival of the Moshiach, and the rebuilding of the Beis Hamikdash. It would behoove all of us to take a closer look at these brachos and give them a greater focused attention as we say them and think about their meaning.
In particular, he suggested the sentence from Es Tzemach Dovid - "Ki lishu'ashcha kivinu kol hayom" - "For Your salvation we hope all the day." Meditate on what it means to really desire HaShem's yeshua, and how we can actively hope and pray for the final redemption.
I think both of these ideas are very helpful in transforming these 3 weeks from a time of complaining for lack of shaving and music, to a time period of meaningful reflection wherein we properly utilize the time Chazal has emphasized is a time frame to focus on mourning what we have lost - and what we hope to have - G-d willing soon and in our lifetime - once again.