Stay or call it a day

[unicorns1]

Please be gentle it is my first post, I just need some advice...
Been with my BF for almost 2 years, he has 2 kids who I love dearly, usually things are great between us, we are best mates, talk openly, see a lot of each other and go out all the time with and without the kids.

Lately we have been arguing a lot! It started because I falsely accused him of hiding his phone which turned out to be absolutely innocent (I have anxiety which doesn't help) We broke up in the heat of the fight and 2 days later we got back together saying the relationship is both what we wanted. We are in a v serious relationship, currently saving for a mortgage and have holidays booked, talk constantly about having a baby
Since we broke up and got back together I haven't seen him for 3 days and he has been totally 'off' in texts/calls, all of which i initiate first otherwise I haven't heard from him.
So I'm at work now and he has text me saying things haven't been the same since our argument and he no longer wants to be with me?? I have put nothing but 10000% into being with him and taken on his kids with no question or doubt.
Last night I rang him and told him I felt he was being different and basically told me to get a grip because it has only been 3 days that we haven't seen each other. FINE. So then I asked if we were taking the kids out this weekend, he told me he was taking them out alone (I only see them once every 2 weeks so he does get his 'alone' time with them) I am mortified after I have taken them on, I am a lot younger than him so people think I am insane lol plus I miss them when I don't see them
So now that he has text me I called him as I can't be having a text-off at work. I basically said to him how I felt about him being offish and not prioritising me and not involving me in his plans this weekend.. anyway now we are meeting later to TALK. This is make or break for us as I am not continuing like this. We have argued in the past we've always just bounced back..
I guess I am just asking like what do I say and what boundaries do I set so I am not the one making all the effort?
Thanks, sorry it's so long

He has already said that he doesn't want to be with you any more. That is enough. Don't beg or plead or do the pick-me dance. It's over.

This is the end.
He's lost interest.
He may have found another interest elsewhere.
What is the age difference?
Do not beg or plead.
Remain strong on the outside.

X-Post - same words used as well.

I think the arguments and your need for reassurance and an explanation to his hot/cold behaviour (which I think you are completely entitled to) has taken the shine off things for him. I would personally step back and not contact him at all for a few days unless he makes the first move with it. That’s always a good test to see if someone wants to make things work or not. If he realises he’s making a mistake and wants you back then the time apart and silence from your end will give him time to think and miss you. If he still wants to break up and isn’t interested in reconciling then he’ll not make any effort to be in touch and you’ll need to think about moving on