'True Blood' Star Rutina Wesley -- Marriage Sucks ... Files For Divorce

"True Blood" star Rutina Wesley is ending her marriage, but she's taking steps to make sure she's not sucked dry ... TMZ has learned.

The actress -- who plays Tara on the show -- filed divorce docs to end her 8-year-marriage to actor Jacob Fishel ... citing the go-to reason -- irreconcilable differences.

Rutina is more successful than Fishel and presumably pulls in a lot more bank, but she's asking the judge to reject any claim he might make for spousal support.

Rutina and Jacob met at Juilliard back when they were students ... and tied the knot when they graduated in June, 2005. They have no kids.