I agree that it is important to talk to your therapist. Only they will be able to help you wade through all of these issues. It sounds like you're very confused, and being very triggered right now. These different symptoms can get much worse with stress, and since it is the holidays, it makes sense that things are a little tough right now. If you've been dealing with these issues for years, it sounds like you are not getting the support and answers you need. This can be for many reasons, including misdiagnosis, medication needs/issues, your health professionals not having all of the information, not having a good match of professional supports, etc etc. The list goes on.

Most important is for you to take a breath. Remind yourself that you are the same important and good person you have always been, right from birth. If you do have different personalities, they are all parts that make up that wonderul person that you are. If they are simply different moods/aspects of you, they are different aspects that make up that whole person.

One suggestion, if you haven't brought up these important thoughts to your therapist, is to write down a symptom journal. Try and be as specific as you can about when, for how long, and how extreme each symptom is, along with describing words and your feelings at these times. Sometimes it even helps to write out comments you hear from other people. In university I had some people suggest that I might have bipolar because 'sometimes I got so hyper it was like I was a totally different person'. I was a different person(ality) at the time, just not because of bipolar, it was because of trauma.

Having this information written out can help when you're trying to explain it all to other people, or when you're trying to figure things out yourself.

I have been trying to keep track of different aspects of my mental health, so I got some cheap subject notebooks, each a different colour. One I keep all my notes for my dr, one for my counsellor. One I keep messages from my different parts, or notes I write to the parts to communicate, and one I keep all my flashbacks and new memories in (I am working through past trauma and writing them out keeps them from going around and around my mind - I only open this up to read when I'm in session, and only open it to write in it when I'm releasing the memory. That way it remains safe for me). You can use your own method, but it is helpful to 'store' the information so you don't have to keep remembering it. Like writing down a grocery list helps you remember what you need, without having to constantly remind yourself of it. Trying to remember symptoms for appointments and for yourself to later make sense can be similar. If it's written out it's accessible and you don't need to constantly have it in your mind to have that access.
If words are difficult drawing, art work (collages, colours, painting, etc) can help you journal as well.

I wish you all the best. It sounds like you're very anxious right now (and have every right to feel that way). I hope that you can be somewhere safe and calm, and that you have some supportive people to talk to.

All my best,
IJ