Noddy, I think that's an excellent idea!
You may find that out of habit; you are doing many things you don't even like! If you could have anything for breakfast; what would it be? Go ahead and get it for yourself!
I would strongly suggest carving some time into EVERY day; even if it is only for 10 minutes to start with, where you do something YOU enjoy. What you enjoy may be anything: So long as it is what you like, that's the ticket.
I have definetely had to LEARN optimism. I was a serious gloom-and-doom character for a long while. Don't expect big changes over night; just steadily plod away.......and don't forget to laugh WHENEVER YOU CAN.
When we're stuck in negativity; we tend to take things a wee bit too seriously.