How to handle separation with kids?

Question

Any and all advice is greatly appreciated! 
My ex and I have two kids and are officially separated and living apart. Prior to my leaving, we discussed the schedule would be he gets the kids on his days off and the night before. He didn’t want to take them during working days bc “it’d be too much for him to get himself and them ready, drop them off and head to work” and he has yet to get a second car seat.. it’s a 4 minute drive to where he’d have to go and I work a full time job too so I still have to do the same. He also expects me to pack a bag every time I drop them off and drive them both ways. So I asked that he gives me half of things I buy for them and send to his house. He agreed to it all. 
Going back to last Wednesday, a friend of his who he doesn’t see often, invited him down to the city next Saturday. He agreed to these plans bc it’s his bday next Thursday.. he is off every Sunday, yet he still agreed to go out on a night he should have the kids based on our original agreement. 
So I asked last night if he still wanted to do the schedule where he gets the boys Saturday night into Sunday…. He says “don’t matter to me. Whatever works for you. It’s up to you. Why you got plans? I don’t yet. But it is my bday weekend but idk whatever you wanna do”..
How do I respond to that or manage this? I don’t understand why it’s my decision whether he gets his kids or not. Shouldn’t he be the one to say he wants them over his house or not? I’m afraid if I say I’ll keep them (bc I know he made plans - he just lies a lot) that he’ll blame me for him not seeing them and he’ll likely sleep the day away Sunday so he won’t see them for over a week. And I’m also afraid of this becoming a habit where he just leaves them with me bc he wants to go out drinking with his friends. 
We’re in our 30s.. he doesn’t buy anything for his kids but always makes sure he has the nicest clothes and shoes for himself. He doesn’t cook or clean. He goes out drinking 3 nights a week… I know he’s looking forward to being alone and being able to live his life without responsibility or someone worrying about who he’s with or hooking up with. 
Im just worried he’ll continue to take advantage of me. I don’t want to go to court if we can stay on our agreement. But I’m afraid I might have to. He guilt trips me into not doing it by saying “I know you’ll never do that to me bc you care about me and we can make this work”…. Same with child support. He says he’ll be able to pay half for their needs but yet when we lived together I paid for everything and covered him on bills and food… 
Im not sure what to say or do here at this point. Im so worried I’ll continue to be taken advantage of. But I also have no idea how to respond to the “it’s up to you” response as to whether he sees his kids or not… what do I do? I don’t mind having my kids 24/7. That’s perfectly fine for me. But I don’t want him to throw anything in my face if I do take them. Or he’ll make it a big deal that he has his kids and can’t celebrate his bday and he’ll blame me forever for it…
Sorry for the long rant. Thank you if you’ve made it this far.. Any advice is appreciated!

Answer

Go through the courts. You'll regret not doing that.

Answer

Courts 💯  and court ordered child support

Answer

He's probably in that same pickle, afraid you might throw in his face that he'd rather go drinking than see his kids.
When it comes down to the agreement, make it together but also have it enforced by the court. It's not "taking him to court" but it's registering the agreement you made so that everyone keeps to their agreement. It's good for you and for him, just in case issues arise in the future.

Answer

Yep I agree. With someone like him he won’t change and he doesn’t seem to care if he see the kids or not.
Go through the courts

Answer

Going through the court is the easiest way to keep things accountable and enable him to be financially involved. It doesn’t mean you have to be a snot about it just because it goes through the courts. Many parents have custody agreements in place and then by themselves approach it with fluidity. I have friends that have a 70/30 custody agreement but ir really is more like 40/60 because of how fluid they are with communication, they just save correspondence via text in case something were to ever come up, they can vouch that person was on board at that time.

Answer

Why don’t you ask him if he’d like to have the weekend without the kids for his birthday? I don’t see the harm in him wanting to enjoy that time, if that’s what he would like. In turn, you could make an arrangement for you to have the same time where the kids are with him and you have that time. Or, he may offer similar to you in future, and you would be fostering a positive communication type. 
I agree that you need to set a firm agreement together, and should you be unable to differ from that agreement positively when need be, a court order may be best. 
It’s about give and take, in the end you are both going to be in each others lives.

How to handle separation with kids?

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