my concern is that every 4-6 weeks I go into a very deep dark place. I don’t understand why this cycle is happening to me, why every 4-6 weeks I want to run away from my life and not exist anymore (not suicide however I do have intrusive thoughts about myself). Why am I so happy and floating one minute and the next minute I want to scream and cry and lash out. (Again this has been going on a few years not just while pregnant)
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I don’t know if this is depression or there is something more to it. If it is depression does that mean I will need therapy forever and medication forever?? Where is the end in this??
I think I know what it is you want, OP. I think you want to talk to a MH professional who really listens, and takes into account the pattern of your mood changes and all the other things. And then says "hmm - yes this is a typical presentation of X disorder" and then offers the specific treatment for X disorder, which has been developed for people with symptoms exactly as you describe.
You feel they are missing something by saying it's depression, as what you experience is not typical of depression. It's incredibly frustrating dealing with them, as they don't seem to acknowledge this.
The problem is, there isn't actually a specific disorder/issue that presents as you describe. Although some of what you describe sounds like it could be in the ballpark of OCD. But the recurrent depressions - no. So services try to fit you into the nearest option.
I'm slightly hesitant to write the next bit, as I am concerned you may take it as an answer, when really it's just something to consider, whether to rule it out or investigate more. But I would suggest you find out about how autism and ADHD (or ADD - no hyperactivity) present in women. Especially late diagnosed women who you'd not necessarily think were neurodiverse if you met them.
To be apparently managing fine and then break down, repeatedly, can be caused by the sheer exhaustion of functioning in a neurotypical world, if you are neurodiverse. When you break down (or burn out) you retreat a bit, take it easy, the demands on you drop, and so you recover and get back to normal, only for it to happen again.
If this is relevant to you, I have to warn you that it can be hard to get diagnosed on the NHS as an adult, and that if you do get a diagnosis there are basically no services or anything. It just helps to be able to put a label on it to explain to others and to help you understand yourself.
But what you could do, if it seems a possibility, is find out about what helps and try to do these things, to see if they help you. So for example, learning your personal warning signs that you're getting worn out and need to take it easy a bit to prevent a mini burnout. To be honest, this might help anyone actually!
I will also add that it can be very difficult to unpick what is trauma and what is autism, and in some ways they go hand in hand. Also OCD can often develop in autistic people.