Marriage and harmful behavior the choice needs to be made this time.. the choice to actually solve something?

my insomnia has gotten worse and worse..

I know the root of my insomnia and its clearly a bad marriage

being with someone who mistreats me and constantly makes

me walk on egg shells i have decided to stay put for the kids

Before everyone tells me the ill logic with doing that I will tell you

that i remain in this shitty ****** up situation so that my children

are protected from a very irrational emotional loose cannon that

which is my wife. My oldest Step Daughter has seen this inconsistency

that is her mothers mindset and has of course rationally acted out due to

the very unhealthy nature of my wifes narcissism.

Anyways basicially I have due to her and proclaiming my commitment to

my love for her and devotion to her over the years I neglected friendships

and neglected and family to show her insecurities were false. needless to

say I am 5 years paying for insecurities from problems from other men

before me I have had enough

If someone like me (without friends and family) trying to escape a situation

that is clearly a nightmare for everyone and the children involved now.

Do I risk it all by ending this misery with a divorce fully knowing that

things will never get better..

And how do I leave my kids in the hands of a woman that is by all

means a endangerment to their sanity and try to end the cycle that was

passed down to her from happening to my kids.

I am just a rational person on the edge trying to solve a huge problem

that takes several rational people to solve in most case while having a

destructive person continue to make it impossible to actually solve.