Is ex husband regretting divorce? I am really confused?!

We were married for over 7 years and we have a 2 year old son. Overall, with our ups and downs we had a good relationship. He was diagnosed bipolar but it was manageable. Recently though he had a manic episode which I had never experienced. He turned into someone I could not recognise anymore. He changed radically in a month from wanting to have more family and telling me how much he loved me to telling me he wasnt in love with me because there was no intensity. He wanted us to remain just friends. In a moment of anger he kicked us out of the house and I applied quickly for divorce.
The first meeting he was arrogant, vain and self - centred but when we actually signed divorce on the second meeting I started seeing a glimpse of his old self. He is now sad (though I dont know exactly why).
Ive built a massive wall and I have told him I didnt want anything to do with him. Didnt reply to any emails, I have been cold, harsh and distant.
Seeing him down and different has made me realise how much I miss him and I am really confused. He told me he wants to seek help as he wants to be happy (something he wasnt admitting at the time., he was totally fine). I told him all his decisions were rash and he needed to give it time but I do not know if he is missing me. There was nothing wrong in the relationship, we really had no big issues to throw it all away. Is he having second thoughts? Please help!
Added (1). Yes, you are right Jay. Is impossible to know. I just dont want to make the first move. I am terrified.
Tammy, you are right as well. I am probably been nostalgic and want to see him regretting but has said nothing to me about it, even if he may be actually being regretful. This sucks!
Added (2). Sheloves_ Absolutely right. I thought I was making a wise move. My parents had a terrible relationship and never divorced. They continue living together in horrible terms. So I ran opposite direction to avoid "repeating same mistakes"! Unfortunately it was rash too.
Joni. He isnt at the moment. He stopped medication (very natural for some bipolars) and he has said he wants to start doing whatever it takes to be good and happy. I wouldnt like to jump into anything until I see that changes.

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