Oh yes, there are many cliches we could share such as: 1) you have to be a friend to make a friend, 2) you have to love yourself in order to really know how to love another, 3) no man is an island, 4) others don't make you unhappy, you choose to be unhappy.
I think more accurately the wisdom that I have acquired at this late age (50+) I wish to share with my younger friends, colleagues, children and grand children is:
The driving force for this epiphany is the very real possibly of a young, insecure, unhappy, depression-prone young person that I see going down a dark spiral and I cannot FIX what is broken. :(
You Are in Control of Your Own Life
Passively waiting for life to happen to you, or that one other thing that you wish would happen, just one more thing....and you'll be happy.
I believe that a LOT of what life has in store for a person is based STRONGLY on ones own fortitude. If you want to be a rock star, then do what it takes to try your best to be a rock star. Of course, one can want to be a rock star, but might not have the talent to warrant the wish, but that's not the point... It's important to TRY and put EFFORT into making a life that you want, even if YOU fail at least you TRIED (many millionaires fail before they became millionaires).
Isn't a life alone half lived? Don't be filled with regrets of woulda, shoulda, coulda. You don't have to be one of the them. In fact, along the way you will be amazed at the experiences that you gain from the adventures you have in developing your full personhood. It's a journey of discover that should be lifelong with endless possibilities. A clean page to start anew EVERY DAY!!
You Are the Reason You Are Sad
This reminds me of a conversation I had when I was in my early 20's with my boyfriend at the time who was in his mid-30's. He told me with an air of superiority that there isn't just ONE person out there for a single person. In fact, he went on to say that one could really be happy with anyone. Take it one step further, others do not make you sad, YOU make YOU sad (or happy or angry or whatever). Well, I didn't agree with the 'you can be with anyone' theory, but I now do understand what he meant about others not being responsible for your happiness or lack thereof.