I recently broke up with someone after nearly 18 months that almost fit this dynamic exactly, only she's 31 and I'm 35, age wasn't really the excuse.

We really loved each other and would have so many good times, but she was never more than a week from getting cold, getting angry, taking out her stress on me, getting so worked up over things, say she's done with it all and we should break up, only to calm down and apologise. We broke up twice, which she kinda forced me to do, but would then show real insight into her behaviour and ask for another chance. I should have stuck by my guns. Apart from that, she mentioned break-up type comments around 30 times in nearly 18 months.

At first I genuinely felt I was doing things wrong, but after time I came to see that it didn't matter, she was using me as an emotional punching bag. Any ambiguity that either we both contributed to, or she caused, would be turned against me. She would skew things to fit her view but totally ignore my feelings and perspective.

She tried to get better but after a year I couldn't take it any more, I internalised her criticism, started getting ill and tired all the time, became depressed. Eventually I began setting boundaries and asking for respect, for her to address this behaviour. This was the catalyst for us eventually breaking up for good.

I guess I'm saying a) age is an indicator but that might not be what's going on, and b) I believe no one should treat their partner with disrespect or dehumanise them. If she's doing that, you need to lovingly but firmly place some boundaries and stick to them.

Don't do what I did and keep making excuses for her. I should have known better at my age, don't make excuses for your partners crappy behaviour.