It looks like you knew before hand what I was going to suggest. But first I would suggest that you see a doctor with the weight loss to make sure that there is nothing else going on.
You really should consider counseling as you have self esteem issues. They can really help you with that problem.
I have a free site that might help you some and another thing I would suggest is a book called Feeling Good, by Dr. David Burns. It is a really good book. The site is:
http://moodgym.anu.edu.au/welcome
I hope that it helps you.
But you said that you didn't want to talk to anybody face to face, but that is what you need to overcome. Relating to people. Can't you see that? It would be taking care of more than one thing if you see a counselor. So please consider. We are not professionals. All that we can do is offer a little advice. But it does often help. And knowing that you are not alone helps. So take that into consideration.
Best wishes,
Hugs, Karen