How can I make my girlfriend feel better ?

How can you make me feel better?  

Stop worrying about everyone else.  

Make it a happy occasion.  Plan a vacation around it.  Take some time off of work, and go on a memorial trip to honor the said dead.  Visit her grave site.  Maybe take a "homes of the stars" tour and see where she lived.  Rent old movies of hers to watch in the hotel room while ordering in room service.  Could be romantic.  No need to cry.  Death can be fun.  Have your girlfriend dress up as the actress while you video record her acting out select movie scenes of the now deceased performer.  Please don't forget to post them here at the mug.  Use your imagination and you'll not only sweep her off her feet, but you'll touch her heart deeply.  So much so that she'll hardly be able to wait for the next diva to die.  Hooray for Hollywood.  Now get out there and live it up, while the body is still warm.

First, You need a new girlfriend.
It's obvious that she has placed a dead actress that she will never meet over you. 
Everytime you and her make love, she will think of that dead actress. Even if she isn't, you will wonder if she is and that will spoil any further romantical feelings of intimacy between you two.

Cunnalingus 

A shtup. (Look it up.) You might enjoy it , too.

Divorce your wife and husband, and marry her.

kill your gf and she can spend eternity in hell with her fav actress