Hello I've namechanged and I'm looking for a bit of advice I guess.
Bit of background - we've been together for 6 years, not married but lived together since preg with DC1. 2 DC aged 4 and 2 years. Usual ups and downs with DC behaviors, who is responsible for what, struggles with in-laws etc and also a period of 6 months where P was unemployed and drinking too much just after DC2 was born which caused heartache and turmoil but that has been knocked on the head and he is now self-employed running a business which is doing OK.
In October though everything came to a head as we have been having really bad arguments since he started his business 2 years ago, coinciding with the birth of DC2. Basically, he was very rarely actually at home. He was always working. Literally he was working 15 hours a day 7 days a week (well coming in for a big lunchbreak at lunchtime so prob 12 hours of actual work a day but I'm at work then anyway). The DC never saw him in the house with me, never saw us as a couple really because it was just "handover time" if one of us had the kids. Never ate dinner together except on special occasions like birthdays. He would leave at 7am every morning and not back until at least 9pm when kids are already in bed. I begged and begged him to cut down his hours, I got suspicious of an affair etc but that was largely assuaged by being able to call him at work (you can hear the unmistakable 'work' noises in the background due to what he works as) so I knew he was actually there. He never did so in Oct I finally had it with feeling lonely and neglected and him never seeing the DC unless for 5-10mins which really hurt. So I asked him to leave. I felt I had tried my hardest to get him to see sense and just ran out of steam and the resentment was unhealthy.
He went to his parents only 5 miles away, and I basically became a single parent to all intents and purposes. It hurt like hell, but started to feel better and more normal after a while. he would see the DC as frequently as he did before (ie hardly ever) - usually just picking them up from activities etc and driving them home was the extent of it.
So just before Christmas it seemed he had a change of heart. I actually had a wobble and phoned him crying one night and he started crying too on the phone and promised to change things and come back. The stipulations were/are :
He has to come home early enough to see the DC and have dinner here at least 3 nights a week, and plan one holiday a year with us.
He has to agree to come home early to look after DC if I want to go out sometimes instead of always moaning about not being able to be oncall to work.
So we set a date of him coming back and starting the new 'rules' at the end of this week (ie after 5th Jan) as Christmas and NY is busy for his work.
Christmas was great - he spent the whole day with us from 2am on the 24th to boxing day and he bought lots of food and spent 5 hours in the kitchen cooking dinner. New Year was also good - he asked his dad to babysit and took me out at 8pm and then left for work next day after he collected DC and brought them back.
But...... it still seems to me like he is not serious about making these changes to be at home more. I've made it very clear to him that there is no way I'm going back into this if he doesn't keep it up consistently because there's no way in hell the kids are growing up never seeing their parents together and barely seeing their father. The 4 year old has already started saying things like "daddy lives at work" to the 2 year old 
. So I think it would be preferable for them if we were clearly separated and they knew he lived with their grandparents and not to have stressed fighting parents (right now they can't tell much difference tbh because he has always left before they wake at 7.30 and not been in til after their bed). he knows all this. We spoke about it on new year eve too and i asked again. Yes he said. But he didn't seem sincere somehow, I can't put my finger on it. And since yesterday afternoon his phone has been switched off. I just don't think it's reasonable to have a phone switched off for well over 24 hours when you have 2 kids depending on you - what happens if he needs to be contacted in an emergency? his parents have no phone, they just use that skype. I know he will say I'm being unreasonable, but this is a common occurence recently - not for whole days - but for like 12 hours his phone will be off - him uncontactable. He will then say the battery was dead etc. Bullshit - you keep your phone charged you don't leave it off for that long when you have kids if it's your only method of being contacted. maybe a few hours yes, or overnight even whilst charging, not all day. I get delivery reports so I know if I text him at 7pm and it doesn't deliver until the next day at lunchtime .
This doesn't seem like the actions of someone determined to be in more and a better "family" person, does it? 
Apologies for the super long post, I just feel so sad at the moment and have been analysing this too much. I know about deal breakers etc and no regular time as a family is most certainly mine now, so I know what I'll have to do if this doesn't materialize or he makes excuses about work etc. I did say no excuses - that I'm prepared to deal with long work hours as long as that regular time is carved out of dinner with me and DC then helping put them to bed and spending time together 3 nights a week -but no excuses cause other self employed people manage to carve out a little time. I just don't want to be hurt again I feel like I've let him in again for him to hurt me all over again.
Any wise words? If you have got this far that is! x