Yes, I understand you. I have been fighting a depression myself for the past months, although it must have gone on longer than that, undiagnosed. I know how it feels, and understand how you just want it gone away.
The direct answer to your question is: Selective memory loss is impossible. There is no way to forget that past year. But there is a way to get over the depression without forgetting.
The insidious thing about depression is that it makes everything seem like an insurmountable problem, and makes you feel incapable of solving it. So of course, you want the problems gone away. But the way forward is not to change the events which happened, or erase your memory of them. It is to learn that they are not really as bad as they feel, even when your depressed mind is convinced that they are terrible.
I know it might seem impossible to you to do so - after all, you are feeling in your bones that they are bad things. But clinical practice, and my own experience, shows that it is very possible. "Seeing the world with different eyes" is a skill which can be learned, just like you can learn to knit socks or play the piano. And there are many things you can do to learn it - reading books, talking to a specialist (therapist), observing and imitating those who have it, talking with others who are going through the same process, practicing your new skill, and having support from non-affected friends and family members who cheer your success without putting you into a pressure trap.
One of the tricky things about depression is that it saps our motivation to do anything, even the things which will heal us. It is very logical: why do something that is hopeless? The important thing here is to recognize that this hopelessness is not real, it is an illusion created by the illness. It's hard to get over it, because it feels absolutely real, but it is possible. If your ability to motivate yourself is so far down you cannot start with something as hard as cognitive therapy, you could start a medication course (st john's worth for milder cases, if you don't take any other medications, or go straight for synthetic antidepressants), which will give you the initial "spark" which will give you the energy to pack your problems at the root.
You will need a long time until you start feeling normal again, but believe me, it does work, even it is a hard, two-steps-forward-one-backward road. And even when the goal is still far away, the gradual progress is better than staying in place.
The result of it will be that you won't have forgotten what happened to you that last year. But the memories will just be memories, which will not make you feel like an anxious, hopeless failure, the way they do now. Right now, you experience them like a barrier blocking your way forwards in life, and want them gone. When you learn to manage the depression, they will be more like a chalk line on your way - you can step over it without it holding you back in any way.
Many of the resources you need have to be found locally, but I can suggest a few books. I have read tons of them in my own healing process, but these are the ones I found most helpful.
- "The mindful way through depression" by Mark Williams. It is a straight depression self-help book, and the program outlined there is worth it. But even if you can't bring yourself to go through the program, just reading it will bring you valuable insights.
- "Performing under pressure" by Hendrie Weisinger and J. P. Pawliw-Fry. When you are depressed, your problems seem much more overwhelming, while the energy you have to deal with them goes down. Learning strategies to make the best out of your limited energy is very helpful, and can bring you into an important positive feedback loop - the more problems you solve, the less hopeless you feel.
- "The gifts of imperfection" by Brene Brown. Depression makes us feel flawed, like we have failed at being proper humans. There are schools of thought which support such conclusions, and this book exposes the errors of these ways of thinking.
- "On being certain" by Robert Burton. We grow up believing in, well, our beliefs. But a successful cognitive change requires us to recognize that some of our beliefs are wrong, no matter how right they feel. This book is probably not for everybody, and it does not address the problem of depression directly. But once you realize that there are cognitive illusions, just like there are optical illusions, it becomes much easier to understand how a cognitive behavioral therapy or a mindfulness training works, and to not dismiss it as mumbo jumbo from the start.
Good luck with your journey. And don't forget: you don't have to be special, or a super hero, to get over your own depression. All you need is the knowledge how to do it (I listed the sources above) and the tenacity to not give up when it feels hopeless.