I have one close friend I talk to daily and is the only person outside family I can talk about almost everything MH wise to, I've known her about 10 years but we've never physically met (I'm scared she'll hate me and I'll lose her) she lives on the other side of the country. I constantly worry she'll get fed up with me and leave me like everyone else does. But I class her as a close friend because she's always at the end of a text, has helped me through a *lot* in the past few years and we send Xmas & birthday & random presents to each other.

I also have two friends who used to be close friends who I've known nearly 15 years but have drifted away from me but I don't know why except that my mental health has been worse so maybe they just can't cope with that. I used to hear daily from one and every few days from the other but now I go weeks or months with no contact from them despite me trying. The loss of one of them in particular really hurts because I thought she understood and we were very close, visiting all the time, etc.
I have a couple of 'online' friends or old friends I only rarely hear from via email/Facebook who I guess you'd probably bracket 'acquaintances'.