Being a perfectionist and trying too hard can make things harder for you. You seem to worry so much about whether you are doing the right thing or messing up something that this already can make you feel worse. Trying hard can be a strength in terms of you being really dedicated and serious, but when done excessively (as in trying too hard) it can also just make you feel inadequate and drained; like nothing is ever enough. You may need to shift your focus to all that you can give yoursef credit for; all that you have achieved so far. And you will need to support yourself.
However sometimes when things are real tough I find that it is necessary to acknowledge and express all those negative feelings. They are usually not going anywhere no matter how much we ignore them. So what to do? I find that writing helps; to give a voice to that desperate feeling that wants to give up. Write down all that goes through your head without sensoring. Be as miserable or infantile or dramatic as you need to. You don’t even have to worry about forming proper sentences. No one is ever going to read what you wrote. I would also advise against reading it afterwards yourself: the point is to unload yourself of those thoughts by writing them down, not to dwell on them. I usually use loose sheets and throw away what I’ve written afterwards.
I’ve adopted this from a creative tool called “morning pages” where the point is to use stream of consciousness writing to cleanse the mind of the thoughts that may haunt you but that are not useful for focusing on your creative work. This has become an important part of my healing journey now. I think it is important to express the negative feelings that just circulate in your head and make you miserable; get to know them. Sometimes no matter how much we focus on doing the right thing, trying our best and thinking positive, if there is an underlying negative belief our efforts are dissipated. It is good to get to know what those underlying beliefs or negative thoughts are in order to learn to deal with them. Sometimes it is enough to just express them and they have less of power over you. Other times you may come to important insights that can help you in your healing.
If you still find yourself dwelling on these feelings, then you may need to practice cultivating the opposite: that is, focusing on all that is good, all that you are grateful for, all that you are proud of having achieved in your healing so far. Even if you feel really bad, challenge yourself to find at least 1 thing that is good right now. I am usually so fixated on obsessing over my bloated belly that I need to remind myself that even though I am still bloated, I have gotten rid of all my food allergies. So obviously something positive has happened. Focusing on the positive takes practice.
I think both of these things are needed though: expressing the negative, AND, cultivating the positive.
And just make sure you are eating enough. Starving can make you depressed. And if you are already depressed it is even more of an effort to prioritise cooking and eating. In my experience eating well and often enough has made all the difference in terms of stabilising my moods.