Self-belief doesn't just magically appear, it's not something you can turn on or off. I'm suggesting that you take some sort of action to better your life in some small way. Do different things, try new ideas, work towards something you enjoy. Create opportunities, find ways to help others, be nice to yourself. Spend hours, days, weeks, months, years doing things differently. It's extremely hard work and full of setbacks, like I mentioned, but it can be done, and this is how your life changes for the better. In fact, it's the only way life gets better. You'll see once you start taking action.