It's "learning how to..." rather than "learning that...". Good self-help books can provide a framework to understand how your own childhood development influences your current behaviours, and how you can work to change. I'm currently reading "Parenting from the Inside Out" which goes into both the psychology and neurology of the developing brain, and explains how insecure childhood attachment can propagate across generations. I have a mixture of dismissive/avoidant and anxious attachment thought patterns, and it's been helpful to put this into context by reflecting on my own childhood and where they might have come from. Those patterns gradually feel less like something I'm "stuck with" and more like something I can challenge and master.
That's awesome personal insight. My next door neighbors are childhood psychologists and when my daughter was 18 months old I mentioned I was trying to be very intentional about creating secure attachment and the things I was doing to facilitate it. They said in a very supportive and amused tone "oh it's too late, the attachment window has closed by now" then after a long pause said "she is fine and clearly has secure attachment to you and her mom"
By I myself have done a lot of work to understand ways to shift attachment styles similar to yours.