Last nights argument I was very loudly shouting and I am beyond sad and disgusted with myself to say the police were called.
Well he should probably have bought you a gift, but that sounds like a pretty small issue compared to you getting drunk and losing your temper in a totally unacceptable way in front of your children.
It's really not for you to decide that it wasn't all that bad for them, and to insist they were never at risk of any physical harm. You were clearly too drunk to be in control of yourself or your temper, so probably not fully in control of your memory or all of your actions either. People NEVER call the police to their own home to deal with a domestic incident they'd rather the neighbours didn't see or hear, unless they are genuinely fearful for someone's safety and feel they have no other option. Besides which, the emotional harm to your children is damaging too. It's not just a case of 'Well I didn't punch anyone, so no real harm done.'
The first thing you need to do is own it and take full responsibility. That doesn't mean minimising your own behaviour in order to focus on how sorry you are feeling for yourself right now.
Under the circumstances I don't think anyone could blame him for packing his bags and walking. He must be absolutely mortified and frankly ashamed of you.
Also any relationship that is 4 years old yet still involves arguments over multiple exes due to your 'insecurity' is a dysfunctional relationship anyway. I couldn't stand to live with someone who was constantly giving me grief over over past relationships. It's no way to live. If you don't think you can trust him partner then leave. If you can trust him tehn whatever else he did and with whom, before he met you is none of your concern. Don't make both your lives a misery by harping on and on about your insecurity.
Women who do this always make it all about them. The poor, helpless victims of their own angst. Oh but I can't help it, I have trust issues, I have anxiety, I've been hurt in the past, I really try not to get so jealous but blah blah'
When a man behaves like that, it's called emotional abuse and coercive control and everyone tells the woman to phone Women's Aid and get the hell out of the house.