Hello Succulents: I see this is your first post here on PC. So... welcome to PsychCentral.

I'm sorry I don't think I know what to tell you about this. I enjoy learning about the results of recent research into the workings of the human brain. And one idea I've picked up is that a lot more of who we are, & what we do, is controlled by non-conscious areas of our brains than we would typically imagine. So perhaps there is just "material", so to speak, stored in non-conscious areas of your brain (related to the experiences you described) that is causing you the difficulty you're now experiencing. Plus... perhaps there are other experiences in your past that what you experieinced in this relationship triggered.

Of course these are just guesses. Ultimately there's no way to know for certain. What is probably of more significance is what do you do about it? One way to approach something such as this is to delve into it with the help of a counselor or mental health therapist. Another might be to employ a practice that is referred to as compassionate abiding. Here's a link to a description of the practice:

Relieve Distress By Allowing It: Compassionate Abiding 101 | Mindset: Perspective Is Everything

And then here are links to 2 articles, from PsychCentral's archives, on the subject of healing from abuse plus 9 articles that offer a variety of suggestions for dealing with painful emotions:

Recovering from Abuse: Collecting Pebbles

Victims of Emotional Abuse | The Recovery Expert

How to Sit with Painful Emotions

8 Tips For Dealing With Painful Emotions | Cultivating Contentment & Happiness

https://psychcentral.com/blog/when-y...dium=popular17

https://psychcentral.com/blog/a-tech...nful-feelings/

https://psychcentral.com/blog/8-crea...nful-emotions/

https://blogs.psychcentral.com/every...your-emotions/

https://psychcentral.com/blog/unders...g-to-tell-you/

https://psychcentral.com/lib/the-hea...of-journaling/

https://psychcentral.com/blog/using-...o-reclaim-joy/

I hope you find PC to be of benefit.