Have been deliberating posting this for months, so thank you for taking the time to read, I would really appreciate some advice.
My oldest friend I've known over 30 years now, and we've been through many life's up and downs. I got married and had children, but my friend decided it was not for her, and pretty much stumbled from one bad relationship to another. She's always had a bit of a penchant for the 'bad boy' type, and used to say it was far more exciting. She has actually commented in the past, that my safe dependable DH is a 'bit boring..but hey ho each to their own'. She could be quite disparaging at times, but I've overlooked a lot over the years.
From the beginning, this friend had occasional odd issues. She would disappear half way through nights out, or simply go off the radar for weeks on end. Sometimes this would be on the back of a manic period of high. She would date some bad guy, usually married..then go to pieces once they ended it. This was a recurring theme. She also seemed to develop a drinking problem over latter years, such that meeting up, was often unpredictable. She would arrive sober & full of beans...knock back a bottle in no time, then quickly morph into some disinterested stranger, where her behaviour would become erratic and embarrassing at times.
In the past few years, she was increasingly becoming erratic. She would cancel things last minute, on some ocassions just not turn up, and on one night out, met a random man and disappeared for the night. Other times she has simply disappeared after pretending to go to the toilet, and has not been contactable for days after. I've really struggled with this behaviour, but I know it must have been MH related, and have tried asking her about it. She is always evasive and simply changes the subject. She has had a particularly bad couple of years, and I tried to help her and be there as much as I could. I invited her on our family holidays, as she used to moan about her brother's family not inviting her anywhere. Although I did try and explain the complexities of that one! 
She sent me a lovely card and flowers early last year, and repeatedly thanked me for being such a good friend, particularly as a lot of our mutual friends and friends she has had herself, seem to have disappeared over the years. Anyway, last year my daughter was ill, and I've had lots of issues too. I've never really mentioned much about it, as she's never been much of a listener, and I'm quite an upbeat person.
Over the course of last year, something changed. We last met last spring. She arrived so happy and glad to see me, and once again, became very drunk very quickly. Said something disparaging about my DH which I ignored, and then had to leave as she had work the next day, and 'some of us have to get out of our beds in the morning'..I'm a p/t work SAHM and the sarky comments about that had become quite common. I didn't hear from her after that for 2 months. (Just for context..she used to msg everyday for many years...typical friends banter). We had a concert arranged with mutual friends, and she contacted them direct, to say she wasn't coming. When I messaged her, asking if she was ok, she ignored me.
She will then send some random msg weeks later. Completely unrelated, and often jokey but sarcastic.
She messaged one day after no contact for weeks, asking if I'd take a theatre ticket she had spare for 80pds...but DH was abroad with work. She messaged back and said ..oh well you'd probably prefer a drinking night anyway, so was pointless of me to ask!! Which seemed bizarre, as while I enjoy going out when I do get the chance, I'm very much the moderate kind!
I had to have two operations, and after the 2nd, I had a text from her in hospital, asking how was life in the land of ladies who lunch. When I told her where I was and why, and explained how I'd been a bit house bound for a few weeks with a long term catheter etc..she sent a bizarre detached one line reply along the lines of...'surely it's not all that bad?!' I just don't know what to make of it anymore. I am baffled and hurt and confused. DH thinks she is mentally unwell, and if she wants to push people away, then there's not a lot I can do. In that sense, I do agree, and I have over the past few months, just stopped trying. I've stopped asking her how she is. I don't call her anymore, as she never answers. And I'd stopped asking her if we can meet, because she simply always ignores it.
Last week got the better of me, I felt sad and thought I'd give it one more try. She had sent one of her random messages, commenting on the snow..and I replied and asked her if she'd like to go for a nice lunch somewhere next week. It had been too long etc etc...and once again, she has simply ignored.
So is this person beyond help? If she wanted no contact, then why does she continue to send random texts every now & again? Should I just stop replying to her?
I have no awareness of MH, although I do get down sometimes myself, I would never be rude to someone, and certainly not in the way she has treated me. People tell me I have been stupid to have put up with it for so long. But 30+ years is a long time, and I miss the friendship we once had. It may have always been peppered with spells of odd behaviour, but the good spells far outweighed the bad. Unfortunately the past few years has just seen a rapid decline, and I feel quite sad and hurt. Does anyone have any similar experience, and am I best just closing the door on this friendship for good.
Thank you for reading 