What is the circumstance under which you accepted the 'gift project'? Were you asked to finish it for someone, with or without compensation? If it didn't appeal to you then you should have said 'no, thank you' at the time of the attempted gifting. Why would you take something you didn't want to do?
If you took it with great intentions and later changed your mind, you can always give it back and say you just really are not finding the time to work on it. End of story.
Or is there some sort of control issue under which you accepted the 'gift'? In any case, if it's causing you guilt, get rid of it.