Not read the whole thread, but this is my experience and why I don't want to get married.
I've been with DP for over 6 years years. One child, we're talking about buying a house and we do have long term plans as a "family"
We both have life insurance of which the other is a beneficiary, and wills. All of which will be updated when we do buy a house.
I am financially independent and have 0 plans to ever be a SAHM (largely thanks to the horror stories on Mumsnet). In fact, I am a very independent person generally and struggle sometimes having to refer to someone else for big decisions. I grew up around a lot of single working mothers which I think has really impacted me.
To be honest, I love him but not sure if we will be together forever as we've had a lot of problems in the past, mostly down to his mental health. So I'd rather not be married cos it would be easier to "get away".
I wouldn't expect a bereavement package from the government though!