Left drunk on her exes car windscreen // I am not a cuckoo

[Mark Cecil]

Left drunk on her exes car windscreen // I am not a cuckoo

Screaming, crying, crawling man This might be only a minor point but all other lines in the poem except this one have 8 syllables just in case you are pedantic about structure
I took your nest because I can.
Her whispered whims no longer yours,
She’s lost yet found; for I she chores.
Displaced, dismayed, I know your pain;
Deserved. I’d do the same again.
The hand you dealt her, boastful, vain,
You wronged her, conned her, yanked your chain.
She wondered, wandered, waning, sane. I don't see how the word "sane" fits in this context it seems to be there just for the rhyme perhaps putting the word "but" before "sane" to make it fit better
Your loss you caused. I made my gain.
But no, a cuckoo I am not I'm not too hung up by this inversion
No chicks were slain, nor laid to rot. Good ending

Edit 1
Screaming, crying, crawling man
I took your nest because I can.
Her whispered whims no longer yours,
She’s lost yet found; for me she chores.
Displaced, dismayed, I know your pain:
Deserved, I’d do the same again.
The hand you dealt her? Boastful, vain.
You wronged her, conned her, yanked your chain..
She wondered, wandered, crazed yet sane.
Your loss you caused. I made my gain.
But no, a cuckoo I am not
No chicks were slain, nor laid to rot.

Overall I really like this poem it has a good structure and flow to it.  Keep up the good work.