[Halcyon]

You seem to be in a settled relationship with your own house together.
A house is a big thing and your partner has decided to do all this with you and live with you.
I don't think you need to worry.

Obviously unlike a computer hard drive we can't format our brains so there will always be memories of the past and past experiences that have happened to you.
It is normal for all of these experiences to get jumbled up in dreams.

If you feel that the past is always coming back and making you feel worried then talking to a councilor about ways you can leave the past behind and focus on your future may be a good idea.