THE MURPH STILL WITH THE OLD GUY.....

Brittany Murphy and Simon Monjack attended the Rock & Republic City of Hope event in Beverly Hills last nite.

Meanwhile,

Among Monjak's troubles: two warrants for his arrest in Virginia for alleged credit-card theft and fraud; an unpaid $6,087 legal bill, and a $502,910 judgment against him by a British investment firm.

He also was jailed earlier this year for overstaying his tourist visa, and Murphy, 29, had to bail him out. "Simon began pushing for marriage, since he was going to be deported," says a source, adding that Murphy paid for her own engagement ring.

WHAT ARE YOU DOING BRITTANY!!!