I'm glad you got to the bottom of what was causing you so much pain (period pain). Wondering if anyone has given you any way to cope with the pain next time around.
I'm so sorry to hear how poorly your friend is treating you. Sometimes people just don't know how to treat us thoughtfully. It can leave us feeling as though there's something wrong with us. In fact, we can be the same amazing person we've always been, it's them who has changed.
Wondering how your pen pal's going. Have you been communicating with him much these days? If not, maybe it's time to get in touch with him and have a few wonderful conversations, such as wondering (together) about why life can feel like a challenge sometimes, what kind of movies you'd like to see come out at the cinemas, why is the sky blue, what gives flowers their perfume. There are so many things to wonder about, it's always great if you can find people who wonder as much as you.
Don't feel too pressured to get your license. As I tell my 18 year old daughter, only get it if you feel there's a need to, otherwise keep traveling in the ways you're happy to. Also, it's expensive, running a car. Don't let anyone pressure you. You'll feel when the time is right for you to get it.
It can definitely be stressful and/or deeply saddening when we're up in our head, doing nothing but thinking, 24/7. Can you think of any activities you can 'ground' yourself in? I find nature to be a great way of grounding myself. I can get out into nature and do nothing but have a pure sensory experience: Pay full attention to the sounds of the birds, feel the breeze and the way it touches my skin, take in the aroma of a variety of plants etc. I believe there are such things as nature groups, where people get together to share this kind of experience. If you have access to a reasonably good camera, this is a bonus (capturing the beauty around you).