Please Help! I Can’t Satisfy My Girlfriend Who Wants S3x Every Night-

My sweetheart needs s3x each night and I don't keep up.I have these emotions she's a nymphomaniac. We've been as one two or three months and there is no sign her fervency is backing off.  It's awesome to have a lady who is so into me however I'm thinking that its difficult to stay keep up with her requests. Now and then it's hard to get an Attention and I'm notwithstanding pondering whether men can fake a climax like ladies do.