Your wife is in great danger! All of her studies will be sins upon her if it prevents her from giving you your rights whenever you demand it! You can’t masturbate yourself but she can do that for you! She has no excuse and stress doesn’t justify her from being intimate with you as it doesn’t involve anything from her part at worse case scenario!

Kindly show her this video:
https://www.youtube.com/watch?v=O1Jop03Gmi0

Sheikh my wife is a Dr and is stressed about her exams and doesn’t physical get involved with me for months and it is frustrating for me.. I tried to fast but no help and to marry again I can’t as it is not at all accepted in our culture…So what should I do?? Can I masturbate so I will be away from sins as it becomes v v hard at times