As I have had a severe manic episode, just one, i was diagnosed with bipolar.

Then it was changed to BPD. But now my psychiatrist has a good few years of my mood swings and symptoms to go on, she thinks I either have cyclothemia or bp2.

I definitely identify with cyclothemia more than full blown bipolar. Sever mania doesn't happen at all to me, when it did happen was 7 years ago and that could have been the result of the medication I was on and the BPD.

However I do find that i experience a mixed state often which doesn't fit with cyclothemia.

I feel bipolar and BPD and maybe other diagnoses are just one massive spectrum send few people ever fit perfectly into one diagnosis.

That's why psychology tends to treat the individual symptoms nowadays rather than the overall diagnosis.

Have you been diagnosed then?