First of all congratulations. By losing your boyfriend, you have lost pretty much everything you ever had, correct me if I'm wrong. This is the very essential thing that has to happen in order to change your life, there is no way you could've done it on your own just "out of the blue". There is always a "kickstart" and ironically, most of the times we perceive it as negative or bad, while if we only knew what the future is, we'd be extremely happy for it, even if it hurts like hell right now. As you probably realize by now, the end of your relationship is a beginning, an opening to a whole new world of possibilities and happiness. Only now you are beginning to "wake up", but don't get overconfident, it is a very long, hard journey and you really need to understand your mind and how it works in order to actually be able to put up with depression, loneliness etc.
The ideas that you brainstormed are really all good, but you should first start by setting a goal for yourself. A life purpose. Now you don't need to decide for ending the world hunger right away, finding your life-long goal is also a proccess that takes time. However, set a simple, realistic goal that you really feel passionate about. Something that will keep you moving even if there is nothing else. Something that you are willing to suffer for, endure all the mental and even physical pain.
You need to have a direction. A crystal clear goal that you are moving towards. Without that, you will never be able to keep up with the things you listed. Without a goal, a purpose that you are passionate about, you won't be able to put up with everyday struggle.
I strongly suggest you follow my own website (for now it's merely a blog) - the link is in my signature. Also, I would like to point you to a very important article that you should read (no, it's not mine or anyhow connected to me - I'm not advertising myself, I truly want to help) http://actualized.org/blueprint/life-purpose while also you can read or watch any videos from Leo (actualized.org) - he knows what he's talking about, and he's covered basically all of the topics or areas of self-development.
What is most important though, if you give up, if you give in to the depression or loneliness, that's the point when you fail. So until you give up and stay strong, you will always win - no matter what. Keep this in mind.
Good luck and have faith in yourself. We are biologically wired to be selfish - so please, be selfish and do everything in your powers to stop thinking about the past, including your ex. Think about yourself and how great you are going to become. Stay positive
There is always something good to gain from adversity in life. A few additional things I would suggest is that these goals can be very vague, which may create resistance in your ability to achieve and make them daily/weekly habits.
Spend time outlining key and detailed ways of achieving these goals.
I'm sorry for your situation, but think that it is GREAT that you're doing something (many somethings, actually) to make the most of it! As my husband always says, "Never waste a crisis," so find a way to learn from it and become better and you'll be unstoppable. Good luck to you!