Our minds have three basic levels. Understanding these levels will help you to know where your past-life memories are stored.
The Unconscious Physical level is the level of reality that stores information and programs for physical matter to exist and work. It is here that the instructions lie that keep your cells dividing, keep crystals knowing how to grow, keep DNA ordered and molecules from having an identity crisis.
Here is the innate intelligence of physical matter. You may not think that your cells are intelligent or that a plant is conscious but look deeper and you may be surprised. This level of your body is programmed for survival. It will relay information up to your Conscious level if action needs to be taken for survival. It will try to direct the conscious level in a way that secures physical survival.
The Conscious Physical and Non-Physical Mix level is where you live mostly. You know yourself as an existing being. You receive data and prompting from many sources, but mostly from the Unconscious Physical and the Superconscious Non-Physical level. This is the level where you can consciously choose to block or open to any incoming streams of data. You do this through Attention and Intention. Where you place your attention or focus is key.
You are being bombarded by sensory data and cognitive data all the time, but you filter out 99% of this data. By changing your focus and setting a cognitive intention you can open new windows of perception and knowing.
The Superconscious Non-Physical level holds the knowing of your soul. The memories of all other lives, the knowledge of your multidimensional existence. It is non-physical and breaks the laws of space and time. Hence at this level past lives and future lives are all learnt from simultaneously. Your conscious mind can access information from this level but needs to understand that this data is subtle (versus the raw load physical data) and requires a peaceful state of mind. Your body sometimes picks up on information from this immortal mind, and may not have a reference for it in this lifetime, but receives the impression nonetheless.
If it picks up the impression of a past life in which you died in a fire, it gets the impression that you should fear death and may even receive the feelings of pain associated with fire. This will generate a fear response in your body, whenever you think about and especially when you are near fire. There may seem like no logical explanation for the fears or the familiar attractions you have to places, things and people, but your body gets the superconscious impression none-the-less and responds accordingly. So once again we remind you to pay attention to your feelings and to the spontaneous subtle impressions you get in your day to day life and relations.
Note - there are gradients for all 3 levels, from the most physical to the least.
What we want to consider now is when past life experiences, and even those from this lifetime, interfere with current life goals. Why do you suppose you forget your past lives? Let's see. Here is an imaginary example. Let's say that you and another soul make an agreement to balance some learning originating in a previous lifetime. You make this agreement out of love and then incarnate. At the time in your life when you meet this person, you may get that familiar feeling or an urge or nudging to connect with them. Imagine that your agreement is to potentially develop a relationship, which you do, and events unfold that result in great learning for both of you.
Your souls are grateful for the opportunity to learn and experience. Then it's up to you to take the gift from the experience and learn, or to set a new cycle into motion where you seek to continue to stay stuck in the learning experience. Now can you imagine meeting this person and before you even begin the relationship you have clear memory in detail of the time she betrayed you, or the time you abandoned him, etc? This may interfere with your current life purpose.
You will get glimpses of past lives when it is appropriate for your learning. It may be helpful to understand the patterns in order to break them. It may assist you to understand the meaning of an event or feeling. Trust your soul to guide the process and to reveal what is of benefit to you now and to keep veiled what is of no benefit to you at this point.
Consider this. We walk a long road as souls, appreciating every experience. We have been the victor and the victim, the thief and the one stolen from. That is what makes us whole. It completes our experience and allows us to develop the wisdom, love and compassion that we seek. If you are attracted to healing, no doubt it is at least partially motivated by your knowing what it feels like to need healing. If you know what feeling sad feels like you are in a much stronger position to "be there" for a sad loved one. How do you know the light without having the dark as a comparison?