How do i get my ex back?

My ex of nearly ten years walked out on myself and our two children (6 and 2) on the 24th April. just after that i did the usual texting phoning and writing letters etc.
About a month ago we started to sext, and i agreed to be ****buddies the arrangement was going ok until i thought NO im the one who always starts the conversation off, his responce to that was that he didnt think he should, coz he didnt want me to think that he wanted me back, However i got the main reason he left out of him a few days later (After nearly ten years and him walking out on me and the kids 5 times, the sex had dried up and that he felt that we had got to the point that we were just friends, Lack of spark etc…) also other things like nagging etc.
The arrangement was back on and he came round to spend some time with the kids last night and we had the most amazing sex we had ever had when we together, and it was really nice for me to show him that i have changed because all this has made me realize that the lack of intimacy etc was mostly my fault. And i admit that. But when he left i just burst into tears and have been at the point of tears all day because i know in my heart that it could be really good even better than before if we did it slowly and worked on issues. I want him to want to give it a shot and try to give our family a chance at being happy. I think its worth it when he had said that when we tried before all the other times he came back he didnt try, I want him to see how much its worth giving it a shot.
Over the past few weeks there has been a few signs that he was regretting leaving, But now i dont see any at all, He says that hes glad we can be friends.
I really really want my family back together. I had suggested that we both stay single and date for a while and take things really slowly (which we hadnt done in the past he had just come back and we had not dealt with any of the issues we had)
Hes been living at his parents since he left and he says that he cant afford to find his own place, although hes saving up for a car coz hes just passed his driving test. He gets about £900 pm and only pays his parents £100 pm for his keep. Does anyone think that this is a sign that he has every intention of trying again when he gets told to move out of his parents, coz i know that his parents wont let him stay there for too long.
As for the kids we had an agreement for him to have the kids two nights a week but because of work he could only have them every other weekend, and two nights in the same week so hed have them 4 nights every other week, Because his parents are foster carers hes been told that his kids can only stay there a certain amount of nights so instead of him looking for his own place hes now sacrificing seeing the kids for that one night, Inbetween him having them he doesnt get in touch to speak to them or to see how they are, i have to text him to ask when hes going to see them.

My question for everyone is how do i win him back and what should i do??? I really really want him to give us another chance, i cant and dont want to give up on this coz i know in my heart that if the effort was put in it would work, at the beginning of the split he said maybe in 6 months a year or two he may want to try again.

What advice would you give me??? Any would be helpful (i cannot express how much i want him back) Please help me i need tips on how to win him back!
x
Thanks for the websites, but ive looked at them before i posted this and they dont really help! We are getting on and im not texting him (which is hard)
I saw his status on FB last night and saw that hes loving all this, he gets to have chinese takeaway and play on his brothers xbox all night while im stressing and killing myself having to deal with the kids on my own. Im so pissed off that he doesnt seem to be missing us or even the kids in anyway, coz if he was maybe hed want to try again, but it seems that he just doesnt care and is loving having his own time to do and go where he wants when he wants, although when ive spoken to him he says that hes so bored at his parents coz he doesnt have anything to do with himself. It pisses me off that he doesnt put the effort in to even speak to his kids, I know that if i asked him hed say that hes seeing the kids as often as he can and that it cant be more coz of his work. I just hate that everyone around him is making it easy for him.

This is an unusual one; with the financial and living circumstances; the logical thing would be just to stay with you and the kids. But, by the sounds of things is he’s just looking for sex right now; don’t know if he’s seeing someone other than just you at all or what. After nearly ten years you’d think he would understand your relationship a little more.
Me and my wife occasionally go through dry spells where I would want sex about every night but, she would only be in the mood about once a month; talk about mismatched libidos. But, I came to the terms: I had to either find away to get her in the mood which can sometimes be an exhausting process or, "handle the situation" myself; which I don’t particularly like but, it has been better than going to bed frustrated or, sleeping around outside of our marriage. Sometimes it comes to wanting to learn the other persons "Love Language" but, he would have to want to learn yours to really make this work.
Whatever happens I hope he comes to the realization that his family loves him and needs him and that’s where he needs to be; "through thick and thin, for better or worse."
Try to keep hope in love; good luck.