my partner is not talking to me.....

I am a 43 year old woman in a relationshi of nearly 3 years with a 52 year old man. My man is the survivors of the worst child abuse imaginable and the fact that he is alive today and fairly 'normal' is a miracle in itself. He is very alternative, has never been married, hasn't felt commited to getting married before and is not sure he believes in it. He is abit of a 'greeny', is into crystals and herbal healing etc. He even wears this crystal round his neck which he was convinced would align him with the woman he was meant to be with....me. Our relationshi0 was very troubled initially, it didn't have a very good start, we met on a sex site.....lol, but over the last 8 months or so has settled down to long term and the last 4 months or so have been almost ideal, with him opening up to me more and more, becoming the man i always knew he could be, and we have developed a closeness, passion and affection that neither of us had experienced before. but it was hard work to get to this stage, and my tenacity and refusal to give up has got us to where we are today. He was like a frightened little boy when i first met him, scared to give and receive affection, feeling touch was only necessary for sex and then only the bare minimal. Now he spontaneously touches me, we hold hands, and some times he almost holds on to me desparately over night as if he is scared I will escape. In the initial stages of our relationship, everytime we had a fight he would 'dump' me, saying he never wanted to see me again, would disappear, turn his phone off, but then would rematerialise anything up to three weeks later, in a better frame of mind and our relationship would set off again. The initial times he dumped me, i was devastated, wondering what was going on, and naturally thinking i was never going to see him again. One time he dumped my quite viciously and i naturally asked for my stuff back that i had at his house, and he was surprized wondering why i was taking the stuff with me, but ofcourse in his eyes it wasn't over.
He has a fear of abandonment, and following an argument, due to his insecurities he imagines i am going to 'dump' him so reacts by 'dumping' me first....it is a very strange but common coping mechanism for peop0le with a mental illness.
During the last 8 months our relationship has become serious, we have spoken about marriage (which is a big deal for him.... he has called me the love of his life, his soul mate and the woman he was meant to be with, and this frightened, tragic man, has turned into the man i always knew he was capable of being during those dreadful early months in our relationship. He didn't always treat me right, in fact sometimes treated me quite shabbily....but he didnt know any better. Eventho he has had heaps of relationships before, I am the one that has taught him what love is all about, with my understanding, forgiveness, and steadfastness. He has become an amazing man, he is p0oetic, romantic, he runs my house as well has his own, takes my daughter shopping and on appointments, its undiscribable how special this man is. Finally he is learning to fight effectively and not 'dump0' or run off or turn off his phone, and eventho our fights are more comp0lex than with most other coup0les we genrally get through them quite well.
Over the past probally 3 months our relationshi has moved onto another level, and he has begun talking to me about his battles with Depression and how he turns into a 'dickhead', and becomes angry and unreasonable, and his self esteem hits rock bottom and he thinks he's not worthy of me. I asked him during this conversation if that was the reason he used to run away, because he didnt want to inflict his illness on me and he was scared of me abandoning him and also because he had no money or job or future and i had everything. i was so pleased he was eventually sharing this with me, and i was able to assist him working through things.
A few weeks ago i sensed he was entering a severe down but we were still close as ever, he wasn't shoving me away, but it continues to worsen and we had a fight over the weekend where he let me down severely...i didn't react very well and threatened to leave him, hence a call from him the next day saying he was sick of my threats, didn't love me, never did, and never wanted to see me again....he has turned his mobile off and i have not been able to talk to him since the weekend....he has gone back to using his old mechanisms. Can anybody give me advise on what to do next. We have both made mistakes over the last few days, but i want to say sorry for my role in it and go back to the loving relationship we have been enjoying. I can't bare to lose him,
Why has he gone back to these sorts of behaviours, i thought our relationshi was stronger than that.

things have got progressively worse since I last talked here. He had me up until 2am in the morning sending me abusive textes, calling me names, he wants me to hate him for some reason and I guess again its because he doesn't feel worthy and hates himself. I was going to his house this weekend and for some reason he doesn't want me there, and is trying very hard to halt me going. Why is this when really it is our house, his words, and is my weekend get away....I toyed with the idea that he has another woman, but soon dismissed that idea..David is very loyal and has even remainded with women who have done this to him....he is totally against this....also I'm convinced he still loves me and always will...it is something else, I'm convinced. I told him I was stillgoing to his this weekend to sort it out once and for all and he got really scared and almost desp0arate, and even sent a text to my daughter to tell me not to go to his, and told her I would regret it if I went up0 there, and told her I was psychotic and dangerous. I was not impressed as I did not want my daughter involved. My daughter is as confused as me, and sent him a message back saying whats going on David, i know you don't want to end this relationshi.....I know how much you love mum. She then said to me, mum he is having a severe sychosis, its best you are not around him when he is like that (she had an ex boyfriend with a mental illness....I am now left thinking there is something much more serious wrong with David than deression....How can he change so much in a few days. If I wasn't so concerned about what he may do, I would still go to his this weekend because I am dead curious about what is going on, and want to resolve it face to face. Eventho he has 'ran away' during argument and not always acted right, I have never been threatened or felt scared of him....infact he is a very gentle man.

what is going on? My daughter says don't worry he will be back he always is, and my gut tells me that once he has got over this he will be back, but I'm so worried and wondering if he has a severe mental illness, and if this severe reaction is going to continue