I suffered from anxiety and depression since I was a teen. I had therapy and medication for a few years at university. Medication helped me function, though didn't help me feel better. Therapy sucked for me - I didn't get on with the therapist (CBT) but was so depressed that I blamed myself and thought I wasn't trying hard enough. I'm now 25 and have been OK for a few years (still get the blues and the shivers but nothing crippling) but live with the knowledge that it could come back at any time.
In terms of the MMM site and forum, I spend a lot of time on the Antimustachian Wall of Shame and Comedy. I can't bear the case studies where people are making $100k a year. It makes me feel like shit. So the AMWOSAC helps me set the bar low. It's silly but it helps. I've got the MMM basics/philosophy down now - I don't need to rehash it again and again.
For my personal savings, I also set pathetically small goals. My goal this year was to save £1000 - I made that in February, which made everything I saved the rest of the year feel like a bonus and that I was doing really well. I might make save £10,000 this year if I am really lucky. My goal for next year is to save £2000. I don't believe in stretch goals - they are anxiety producing. I need a goal I can meet pathetically easily. I also do this for my to-do list. I have a 'Must Do' sections which is like 'Empty bin, put away books' and then an Optional section with loads of other stuff. As long as I do the 'Must Do' it's OK but I usually get a good chunk of Optional (real stuff!) done too. Sometimes when I have a bad day, though, at least I've done the 'Must Do'. And it's easier to get out of bed and face t he day when it doesn't seem overwhelming.
I also avoid time-based schedules, even though I love to plan, in favour of sequence-based schedules. So rather than:
9am: X
10am: Y
10.30am: Z
It's:
X then Y then Z.
So I don't have to stress if I fall behind my arbitrary self-imposed timing. And I put the important things first in case I don't finish.
I look at my savings in two different ways. This year the number crept up so that even if I never save another penny, compound interest means I could retire at 65 with our current lifestyle. I crave safety and security and for some reason (even though I grew up comfortably middle class) am terrified of being poor (REALLY poor, like destitute and homeless). The fact that I have 'normal' retirement sorted kind of calms me down, even though I would like to retire earlier and with more disposable income.
For some reason, when I am really depressed the only thing I can do is work. I cannot work out how to eat regular, appropriate meals but I can still work. Maybe it's because it's something I feel has nothing to do with me? Sleeping, eating, washing, socialising - everything goes to shit except for work. However, part of my worry about the depression maybe coming back is that I would need to be able to take time off work. Not sure why I think this but it's ingrained pretty strongly. So I also measure my stash in how many years I could have off work before I needed another job. I'm currently on about five (depending on how the market is doing). That seems like a good long time. So paradoxically even though I would probably be able to work through another spell of depression just fine and would be far too anxious to spend any of the money, it feels like insurance for me.
I'm a huge planner, even though it sometimes adds to my anxiety. I love making spreadsheets of projected savings rates and time to retirement. I don't even know if I want to retire fully but I feel like I need to have the option as a huge safety net. But looking at it all freaks me out because it seems so huge! So I try my hardest not to look at the future but to concentrate on the past - specifically a NW graph of the last few years. I update when I add more money or happen to look, not regularly, and I never add the number to the spreadsheet if it's less than last time. It's kind of cheating and leads to gaps between data points but on the graph it looks like it always goes up.
In terms of what I do to help myself mentally... I'm really introverted but if I'm alone for more than a few days I start going crazy without noticing. So the rule is that I have to leave the house once a day, even if it's just going to the corner shop.
Another things is that when I start getting upset or panicky I have to sit down first and drink a glass of cool water, sipping not gulping. It's hard to cry and drink at the same time (breathing!) and the sensation of the water kind of brings me back. Usually by the end of the glass I am a bit calmer.
For a long time I slept with the radio on at night (Radio 4, talking not music) in case I woke up in the middle of the night with thoughts racing. It's hard to listen to the voice on the radio and the voice in your head at the same time so concentrating on the quiet radio would fade the voice in my head.
Sometimes with mental illness you do need to trick yourself. Work out what freaks you out (me: not meeting goals/schedules) and trick yourself out of it (set pathetically low goals).