Dear Total disbelief~
That sounds a most horrible shock, coming out of the blue and him appearing so uncompromising.
In such situations there is a great tendency to blame oneself for the whole matter, and this is in most cases simply not true. As you say he came home from work, and you may not know what has happened there.
If there has been fighting and yelling in the past perhaps you both have quick tempers and maybe even prone to hasty acts? Please excuse me if I misunderstand.
32 Years is a long time to give up, and it may be that things may work out. I'd suggest getting in contact with Relationships Australia - 1300 364 277 and see what the have to say, they are very experienced in matters like these.
In the meantime can I ask what support you have. Do you have family or freinds that you can talk to who can give comfort and perspective? It does make a difference.
Please let us know how you get on