Decision making in luteal phase

So, this likely won't be a surprise to anyone here, but I feel pretty great in menstrual and follicular phase, and then horrific in luteal phase.

In menstrual phase, I feel quite normal. In follicular, I start to feel hypomanic and perhaps verging on manic leading up to ovulation. I just feel on top of the world. In luteal, I feel extremely fatigued, depressed, overwhelmed and also insecure about everything.

How do you know which feels and thoughts are the "real you"? Eg. I met a man almost 4 weeks ago, when I was in menstrual phase. We hit it off and spent 12+ hours talking per day. Leading up to ovulation, I was quite sure that he's my future husband. I'm 36 and have met many people in life and know what's important to me and we line up on everything, including such nuanced matters. So it shouldn't be purely hormonal. However, I felt a bit too euphoric, perhaps, and I wasn't sleeping. Now I'm one week post ovulation, and with each day I feel more exhausted and depressed. The past few days, I went from being outgoing and confident with this man, to feeling quite insecure and looking out for signs that he's not really that interested. Today, I just feel completely disinterested and I have been looking for reasons to stop dating him. For instance, there may be a couple of things which could make things ideal. Nobody has the perfect situation (let's say I would like his family to live elsewhere or for him to have a different work schedule) and I happily accept this at other times of the month, but in luteal, I start to wonder whether there is a "better" match out there for me. In fact, I mostly start to question whether I can be in any relationship at all. This has happened with numerous people now, and I have a feeling that the doubts I have now are due to PMDD, but I still can't help but feel disinterested, if that makes sense.

This insecurity also applies to work. In fact, the new man and I had decided to work on a project together. Yes, it's very early days because we met under a month ago, and we were just talking about it and planning for the future - not making huge life changes now. However, I felt so confident and excited about this until recently, and the project would involve a lot from me. Now, I feel like it would all be a disaster and I don't have the energy to even get out of bed. I go from planning all of the things and wanting to run 50 businesses to questioning whether I can ever work again.

I suppose this is PMDD, but how do you work through this? Regarding romantic relationships - I hear people picking fights with their long-term boyfriends or husbands. Do you think it means that you were secretly unhappy the entire month but managed to suppress it and now you can't, or do you think the feelings and fears in luteal phase are not genuine whatsoever and just driven by hormones without any backing?

Thanks!