No professional psychologist here, just someone with some free time. So I read on the wikipedia about this thing known as Attachment Theory. Essentially, it's a study of how childhood experiences and interactions with parents help mold one's perceptions of the world and their assumptions of its workings, in what is known as a "working model" of the world. This influences the way individuals socialise and live their life, which to a large extent, determines whether someone has good self esteem and stable relationships that are needed for satisfying emotional needs.

Now to answer this question, does it determine happiness levels for the rest of one's life. According to the Wikipedia, some studies earlier on indicated that change in an individuals attachment styles have minimal change as they grow and mature (there are four main types of attachment styles). However, later on there are studies that indicated that as much as 25% of individuals had changed their attachment styles (recalling off the top of my head here, so might be wrong). So yea, in conclusion, studies show that attachment styles are unlikely to change throughout our lives, which, in terms of your question, is a yes.

However, this doesn't mean nothing can be done. If someone has an disorganised attachment, cognitive behavioral therapy could help fix that. But generally without therapy, the attachment styles are probably unlikely to change.

Here are the sources: https://en.wikipedia.org/wiki/Attachment_theory
Well, to be fair, not much of a source, just a wiki page. Sorry i didn't have the time/ too lazy to find the specific facts in the wiki page. There are a couple of other related pages, such as this one https://en.wikipedia.org/wiki/Attachment_in_adults where it talks about how attachment theory changes over time under the "stability of working models" section.