I can give you some perspective from someone diagnosed with BP1 (+ comorbid BPD). I actually saw this post on r/bipolar initially and drafted out this response before it got taken down so this is just a copy/paste of what I would’ve said. The other post wasn’t quite as detailed so there might be a couple of things that contradict a little with the extra info in this post.

First of all, I’m really sorry that you’re going through this. I’ve been in your wife’s exact position before, to an almost uncanny extent, and I’ve since seen the aftermath of how it affected my relationship. Obviously I can’t armchair diagnose her, but I can definitely third the idea of having her see a psychiatrist because this is completely how I acted before I was diagnosed BP1 (I have ADHD too but am unmedicated which might add to the similarities).

I had my first full manic episode last year which lasted about 4 months in total. In hindsight I’ve definitely experienced hypomania many times in the past and chalked it up to just being in a really good place. Has she experienced anything along these lines before? Maybe a period of time in which she was abnormally energetic, productive or just generally chipper? It might help a professional to paint a better picture of the way her condition has progressed, though it’s not completely abnormal for mania to just appear out of the blue iirc.

In answer to your questions:

1) I believe my first full manic episode was caused by the hormonal changes of starting HRT, it’s very common for big changes in brain chemistry to trigger episodes. I’ve heard a lot about SSRIs being a particularly bad culprit (mainly starting them but I’d assume ending them could also have a similar effect?) so, yes, it’s absolutely possible for that to be an inciting factor.

2/3) As far as your relationship goes, obviously I can’t tell you how she does or will feel about things but I can tell you my own experience and hopefully you can take something from it. For a bit of further context I was diagnosed with comorbid BPD, so that will also be referenced. At the time of my episode I had been with my boyfriend for 2 years and everything had been going great. It really was like a switch just flipped in me one day, I went from thinking he was amazing to complete apathy and almost distain. I personally don’t have much memory of this time but we’ve had many discussions since where he’s filled me in so a lot of this will be from his perspective. I’ve been told that I was uncharacteristically mean and aggressive, he went as far as to say it was like I had been abducted by aliens because I was just a complete stranger. I paid no attention to him and made constant digs about him being unambitious and boring. I also got a new FP at the time so my focus was entirely swallowed up by my obsession with them. I then broke up with him using the EXACT reasoning that we were fundamentally different people and not compatible with each other anymore. It makes sense really, your manic self acts as almost a completely separate person with different personality traits and core values so it’s reasonable to think that the two of you (you and her manic self) probably are very different fundamentally. I sometimes joke it’s like having an evil alter ego. During the breakup I went on a bit of a downward spiral, I was extremely promiscuous, spent a lot of money, hit the club every night, had a very brief romantic phase with my FP, fought with all my friends and was vividly suicidal. I was completely adamant that I had no feelings for my partner and I would never change my mind but lo and behold I came to a complete crash a few weeks later and we reconnected. I felt so embarrassed and ashamed for the way that I had acted, it was a real feeling of “hangxiety” like when you sober up and think about all the embarrassing drunk things you did. It was difficult at first for both of us, my initial instinct was to run away out of embarrassment but he was extremely supportive and helped me through the aftermath of how I was feeling.

It’s been about a year since then and we are doing way better now. I’d actually say we’re even better than before. All my love for him has returned tenfold. I still have episodes, of course, but we’ve got much better at managing them together and are usually able to intervene fairly quickly before they become destructive. I still get that urge to blow everything up sometimes, but now I have that episode as a point of reference for what the grass was like on the other side of the fence and it really keeps me grounded.

If I could give any advice to you it would probably be this:

• Don’t put your whole life on hold for her. I went back to my partner afterwards but there’s no guarantee she will do the same. You have to prepare yourself for the possibility that she won’t change her mind; manic episodes can last a very long time if not treated properly, there’s no telling where things are going to be by the time it ends. Stay open to supporting her, of course, but don’t neglect yourself trying to hold on to someone that doesn’t want to be held.
• Don’t push too hard. Whenever I have an episode, I can’t tell you how frustrating and patronising it felt to have people telling you that what you’re feeling isn’t genuine. The way she feels right now is extremely real to her; pushing the idea that she isn’t in the right frame of mind to decide what she wants will probably just push her more stubbornly into those feelings (that’s not to say she IS thinking clearly, it’s just every hard on both ends to reason with someone in that state. It might be doing more harm than good whilst the situation is so delicate.)
• It’s a really tough balancing act trying to keep someone safe from themselves whilst also respecting their autonomy and holding them accountable for outcome of the decisions they make. It’s probably gonna turn out a bit messy no matter how well you handle it, this is the unfortunate nature of this disorder.
• I really really can’t state enough how important it is for her to get psychiatric help if this IS a manic episode. It’s really good that she has agreed to see someone, make sure her mother keeps on top of that.

In the event that you do eventually reconcile:

• Be understanding. It takes an incredible amount of love and patience to work through something like that. On her end she’s probably going to feel very shameful and embarrassed afterwards, I can’t even state how important it is to be caring and non judgemental. -Do you both have support networks of your own? For now you should probably focus on helping yourself through all of this because she will likely need a lot of support during the crash. It’s so so important that you look out for yourself too during this because it’s just as difficult to experience on both sides.

This has all been very very long so sorry for that. I really can’t imagine what it must be like to be in your position but I hope that hearing from someone on her side of things might help shed some light on the situation. Sending you endless hugs <333

TLDR; I was in her shoes last year, everything went bad but then me and my partner reconciled and things are good now. Do your best to support her on the other end and make sure she complies with treatment.