Hi Jill. This is a lovely place to chat and get help. I would definitely speak to your GP about your mood. I keep a mood diary on an app on my phone. It's really easy and lets me see any trends or even just how stable or unstable it is. If you've been on your Prozac a long there are many newer drugs which might be better but your GP will be the best for that. Is there a craft group near you if you like card making etc.
I'm the world's worst for being lonely but I'm also really bad at inviting people to do something with me. You might be surprised to find some of your friends are a bit lonely too. Xx