My depression is back and life feels hopeless

I have a history of depression and anxiety which affects me very negatively and makes it difficult for me to cope when faced with new, challenging and strange situations.I know how common it is, but sometimes I can't help but feel like the only person in the whole world who's this miserable. I hate myself for feeling like this and just want to disappear.

I recently finished my degree and started working in a job that I took in a heartbeat and thought would be good for me. It's not really what they made it out to be, it's dull and unfulfilling. I'm constantly preoccupied by conflicting thoughts:

I don't want to do this, this is making me miserable. I should look out for my own mental health.

I have to do this, I have to live. It'll be good for me to stick it out.

I'm very aware that this is my first proper job, and the world of work generally is an oftendissatisfying, complex place that I have to get used to. I beat myself up about it, feel guilty for being so miserable, tell myself I'm ungrateful and everyone can see how odd and withdrawn and sad I am. In actual fact, they probably have no idea and thinking these things does me a disservice.

To make matters worse, I submitted my work problem to a newspaper agony aunt recently. It was opened up to commentators who very insensitively proceeded to tell me that I was being naive, ungrateful, knew absolutely nothing about the world and my dreams were pointless. Only a handful of the comments were useful or supportive, the rest weren't even challenging my thoughts, they were just plain nasty. It's hurt me quite a lot.

I'm always pretending to people that I'm okay, but I feel hopeless about the future - that I'll never achieve what I want to achieve, I'll always be crippled by my mental health, that I'm untalented and useless. It's so debilitating and I hate feeling like this. I've never felt suicidal before because I know people love me, but I'm scared that I could be driven to it if my mood gets worse and my life seems more and more hopeless. At the moment I don't want to die, but I really don't want to exist anymore. I want everything to stop.

It's gnawing away at me and eating me up inside. I don't know what to do. I have so many choices. This is my life -I could do anything with it but I'm so scared and so confused.

If anyone has any words of encouragement about their experiences of hopelessness, depression, anxiety and how to cope, I would appreciate it so much. It's making life very hard. Thank you.