I absolutely hate my PhD and I don’t understand the purpose of it I am in the fifth year of my PhD and seriously depressed. In my first year of graduate school I was not funded. In my desperation for funding I chose an opportunity that came my way even though I did not like the topic. The research I would say is pretty mundane, I was providing experimental support for an FEM group. I did t have any freedom until the end of my 4th year. Also my advisor was the co-PI and the project was not in his area of expertise and he had no clue about the work being done. Whenever I get lost and ask him for advice, he would commonly uses the phrase “Do what the industry sponsor wants, keep him happy ”. I literally felt like a contract employee and not a PhD researcher. As expected the work did not yield any papers. My lab mates working on other topics (areas of my advisors expertise) get to present at academic conferences and are writing journals. When I point out this fact I get chided for comparing myself with others and  that my work is “unique”. At one point my advisor himself said that the project was ill conceived. You can understand my frustration.

Now I am depressed, lost, and hardly do anything. I wake up, go to the lab and pass time. I absolutely hate my “thesis”, I don’t have anything meaningful or useful for my future career. I don’t even know the purpose of my thesis topic. initially I was scared to leave, now I feel it is too late to leave.

please advise me on what to do? Thanks.
Now I am depressed, lost, and hardly do anything. I wake up go to the lab and pass time. I absolutely hate my “thesis”


This is the problem; you are stuck in a vicious cycle. You need to meet with your advisor and come up with a solid plan - including a timeline - for what will happen in the next year or two. 

Given that it has already been 5 years, I suspect this plan should involve you finishing your current work, writing a dissertation, and graduating. But, you and your supervisor could also choose a different direction (i.e., starting a new topic or choosing a new advisor).


  I don’t have anything meaningful or useful for my future career. I don’t even know the purpose of my thesis topic. 


At this point it's probably time to decide what your career goals are and make sure your plans are aligned with reaching those goals. 


This could mean spending 1/3 to 1/2 of your time learning skills that will be useful for an industry career, and spending the rest of your time preparing for graduation. Given your level of burn-out, I suspect this is the wiser course, but I'm just guessing. 
Or, it could mean switching topics / advisors / institutions so that you will be competitive for academic positions in topics that interest you more.