Melissa Etheridge's Ex-GF -- I Can't Live on $23,000 a Month!

Melissa Etheridge's ex-GF Tammy Lynn Michaels claims she's barely scraping by on the $23,000 a month Melissa currently pays her in partner and child support -- and now, she wants a massive raise ... this according to new court docs obtained by TMZ.

Tammy just filed the papers in the couple's infamously bitter separation claiming Melissa makes roughly $177,882.00 PER MONTH ... and got Tammy accustomed to an extravagant lifestyle while they were together ... so the $23k is incredibly unfair.

Tammy -- a former actress -- also claims she has "virtually no savings" and would need "extensive retraining" if she were to rejoin the workforce.

Tammy claims Melissa is also brainwashing the kids -- training them to be emotionally distant and rude to Tammy ... and now they won't even give her a hug.

Tammy also accuses Melissa of cursing around the children -- including one instance ... when she told Tammy to "get the f**k off my back" in front of the kids. According to Tammy, Melissa also refuses to let the kids get vaccinated.

As for the reason behind the mudslinging -- Tammy and Melissa are headed into a settlement conference in May to determine support and custody issues ... so it's important for Tammy to demonstrate she's the better mom.