It sounds like you're going through a little PPD, but that doesn't have to be something you need to stress about. You've recognised it yourself, and that's a very good sign, and shows that you're in a good place for tackling it. I would talk to someone about it, your doctor for a start (but don't let anyone prescribe you with any happy pills just for the sake of it - you should try different methods first, especially since it doesn't sound, from what you say, as though you're suffering a very extreme case of this kind of depression.)
It's also a good sign that you're still happy to be with your twins - friends will come back if they're real friends, and as your children get older as well you will start to make some fantastic new friends. All hope is not lost, you just need to work out how to focus on the positive things in your life and squish the negatives. You can be in control and find yourself again.
If you can, you should get outside with the babies - fresh air is seriously underrated and can be tremendously beneficial. A little bit of exercise every day, if you can manage it, will help you to restore some energy and to feel like you've achieved something. It sounds terribly cliched, but it's true. You don't have to visit anyone if you don't feel like it - but you might be surprised: fresh air can work real wonders.
Take care, hope you start to feel good soon.