How to be happy😕

I had a bit of an epiphany today and realized that maybe the reason that I'm having such a hard time letting go of my ex is because I relied on him so much for happiness. Big mistake. I want to be my own source of happiness and to really love myself more than any guy I'll ever be with. I've had a crappy year with all that's gone on in my life and I really want to be happy again because I feel like that happiness will attract and cause positive things to happen. How do I do that?