Quitting research halfway -- how unprofessional/irresponsible? for background: I am a second year Master's student in computer science. I had gone to the same university for undergrad. For my undergrad honors thesis (during last two semesters), I worked with a Professor on a paper which I had designed and implemented, and eventually wrote the manuscript for. The Professor was pleased with the work and the paper was submitted to the top journal in the field. This was over half a year ago. I stopped/withdrew from officially doing research 4 months ago, and two weeks ago the journal got back to us and said the paper can be accepted with major revisions. 

The professor is excited of course, and I had told him that I would be available if further work is needed on this, but I honestly, honestly do not want to do research anymore. I am also in the processes of interviewing/finding a job among some other things, so I have a lot of things on my mind. But it would be leaving unfinished work that I started, and this seems very unprofessional. Since I worked on the manuscript/project alone, I feel like it would be a burden to him and others for me to just drop the paper because I'm "busy". It would also be going back on my word that I would be "available".

Basically, I feel bad. I'm not taking research for credit/graduation requirements, but I just feel bad. I have had trouble concentrating on anything for the past two weeks because this is constantly on my mind.

Question: How can I go about telling the Professor I don't want to work on this paper anymore? It is winter break right now, so I would be telling him over email. The professor is expecting me to begin working on the paper the second week of January.

Any advice or criticism is appreciated, thank you in advance. (Sorry that this is a child-like/emotion-based question, I'm not very good these types of things)
From a mathematician's point of view (I think the situation is fairly similar in CS): It should suffice to leave your research in a state where others can pick it up. For example:


Any preprints that are sufficiently presentable (if not necessarily polished enough for a referee's tastes) can be posted on a preprint repository, if necessary with comments about what parts need changes. If a refereeing process is already underway, and if you really want it out of your eyes, you can ask your coauthors or perhaps even other colleagues familiar with the project to take over the necessary correspondence and editing (although the latter arrangement is unusual). Otherwise, I suggest that you handle communication with referees for all papers you have already submitted.
Any work that hasn't progressed far enough to have presentable results can be handed over to some academics you trust, with explicit guidance as to what can be done with it (e.g., can they assign it to students? finish it on their own? send it to others?) and what sort of attribution you expect (e.g., coauthorship or acknowledgments).


People won't mind you stopping to do research (at least not in math and CS; it's different in other disciplines where you have labs and collaborators heavily relying on one another); but they will mind if you leave a mess of unfinished work behind that they can neither use nor redo, like leaving your clothes in a shared dryer for hours.