I have recently ended a relationship I was in for 4 months with a guy I work with... He was in a relationship when we first started working together but as we got to know each other we built a really good working relationship and we grew to be very close.
I could tell he was very attracted to me (as I was to him) although he never openly flirted and I respected the fact that he was in a relationship so I didn't openly flirt with him either.
Anyway, his girlfriend at the time cheated on him for the 2nd time and he ended their relationship. A month later at a work party we 'got it together'. I thought this was just the natural progression of our feelings and that because we got on so well he would not treat me as a 'reboundee'. The problem with our relationship was (as I've realised now) is that I was the 'reboundee'!
He had been in his ex relationship for 3 years. At the beginning of our relationship he was very 'into' me but as time went on his ex was texting, phoning, emailing at all hours of the day telling him she still loved him and wanted him back etc. so he began backing off from me. Eventually after feeling that he just wasn't 'in' our relationship I told him it wasn't enough for me and that we should end it. He agreed and we talked on the phone at length but the outcome was that he just 'couldn't be bothered' with a relationship and he needed time on his own.
I was very understanding and he thanked me for that and, to be honest, I think I did the right thing for ME. I am not some desperate girl who needs a man to survive so was happier to end our relationship than to stay in it and risk being hurt any more.
I haven't seen him for a month because he's been off work and I haven't contacted him during that time. I see him next week.
My question is... If I give him time to heal and we remain friends, might he realise what he's missing and decide he does want to be with me when he's ready?

You have to decide if you want him in your life as a friend. Because you were friends first, your relationship was short and you ended it amicably you could probably go back to being friends. But I don't think it's a good idea to be friends only in the hope that he becomes interested again. You could end up hurt.

Make an effort to meet new people and continue dating.