I think the best time I ever had was in my late teens when I was so stoned and with friends who were equally stoned, I couldn't think of anything except for the music that was playing very loudly. I was sharing an apartment with two friends. I felt like I didn't have a care in the world and that getting stoned was all that mattered.
That was a time when I felt good about myself. There was also a time in my early 40s that I felt good about myself, but I didn't have close friends.
My wife is in an assisted living facility right now. I wonder if I should get a little pot and get stoned, just for the hell of it... Put on some Pink Floyd or Led Zeppelin and try to relive my youth a bit.