Hi Mike,
I'm sorry to hear you've been feeling depressed. I suffered from severe depression for 20 years (on and off), and I'm hoping it's in my past now, but it's one of those things I'll have to take a day at a time...
My OCD came first. I believe I've had some degree of OCD since I was quite a young child, and it reached its peak when I was about 18 or 19. I didn't suffer from depression until I was about 20, and then it came and went for the next 2 decades. Depression is different to OCD, but both can be Hell.
I've just finished reading a great OCD book: "Break Free From OCD”, by Dr Fiona Challacombe, Dr Victoria Bream, and Professor Paul Salkovskis.
After reading your post, I opened it up and looked for what the authors had to say about depression. They say the following: "Depression often results from having OCD. The level of restriction and interference that OCD causes means that the majority of people with OCD have secondary depression..."
(I assume by that they mean that, at some stage in their lives, OCD sufferers experience secondary depression.)
Depression definitely followed OCD in my own case. (It was like a dog and its master, for me. OCD was the master, and depression was the obedient dog, always just a few steps behind.)
I've really got a lot out of your recent posts, Mike. I can't thank you enough for mentioning Dr Jonathan Grayson. I've read the first chapter of his book, and his website, and I absolutely love his approach to OCD.
As you've gained a lot from Dr Grayson's approach, have you considered using the same techniques for your depression?
What I mean is, if you treat the depression as a result of "uncertainty" (e.g. uncertainty that you will find another partner), then you could try using the same techniques that you would if the uncertainty led to a fear.
Just an idea. Let me know if you've already tried doing that.
You asked if anyone has experienced other emotions in the place of anxiety, such as sadness or depression.
In response to your question, I can personally say a resounding "yes". Anxiety is only one of the emotions that my OCD has led to in my life. My OCD has also caused extreme feelings of sadness; hopelessness; shame; guilt; self-hatred; and lots of other feelings, like sickness (that sick feeling in your gut, when you believe something terrible about yourself), and other emotions...
I personally found that different types of OCD obsessions led to different emotions. For example, fears about germs and contamination led to feelings of physical disgust, not fear. Sexual thoughts led to feelings of self-hatred and self-disgust. Violent thoughts led to sick feelings, and shame. Thoughts about crashing my car led to fear and anxiety...
So each different type of obsession (and I've had lots of different ones in my lifetime) tended to lead to one type of emotional feeling, but that feeling was only anxiety for some of the obsessions. For other obsessions, there was some anxiety, but stronger than the anxiety was shame, or disgust, or revulsion, or self-hatred...or something else, depending on the obsession.
For me, depression became as big a problem as the OCD. Depression was what I knew I had. OCD was what was underneath it, and was the cause of the depression -- but my OCD was undiagnosed for many years, and so was left untreated.
I hope you start to feel better soon.
All the best.