1st: Get of the drugs... pain killers are dumb and just fuck with your mind
2nd: LISTEN to her needs and wants..she gets up early, she tired from school...make her a nice dinner and draw her a bath..a little bath salts and oils..candles...give her some "me time"
3rd: When she's all done..dry her off..have a nice heated bottle of oil/lotion ready for a nice relaxing massage. what drives my wife crazy is having her arms, hands, calves and feet rubbed..
4: Don't push the issue of sex...by this time she will either be in the mood, or ready to fall asleep, but let it happen.
repeat as needed.....your not going to get laid every night, but I get laid 5-6 times a week by taking care of my women first. Show sincere interest in her and how she feels and she will get in the mood more often...
And STOP being paranoid about another man.!!!!