I always explain to new clients that I see the ultimate goal of therapy (well, at least in terms of how I work) as being 'SELF-ACCEPTANCE'. You see, self-acceptance is the key to true change and real change can only come about in a meaningful way when you become who you really are and not who you think you ought to be.
There are many reasons why people struggle with self-acceptance, which might originate from things that have happened to them, things they have done, things done to them or beliefs they have about themselves, which might actually be other people's beliefs about them but they now own them as their own.
The first step in accepting ourselves is finding some understanding or explanation as to how we have come to be the way we are; what life events might have lead to us feeling unable to accept ourselves? This first step is important because it will help you to make links between the past and the present. The next step is to try to see that you adapted as best you could (as we all do) to the experiences you had and that most likely, for a time, this probably worked to some extent; it might have kept you safe in some way, either physically or emotionally or both. This second step is not an easy one, because it asks you to view yourself in a non-judgmental and compassionate way; as someone who did the best they could with the tools they had. This is where a good Therapist can help; they can reinforce the fact that you did your best and will not judge you and they might even challenge you to find some compassion for yourself, however small.
This brings us to the next stage, which is expressing the feelings you have about the events/situations which have lead to you feeling unable to accept yourself; you might feel anger, sadness, shame, disgust or any number of emotions. Exploration of your emotions are part of the healing process; the 'inner child' gets to say what he could never say at the time and the adult you (and perhaps your Therapist) gets to stick up for the inner child and reassure him/her that they have an ally on their road to accepting themselves. You might not want to feel the emotions but denying them is just perpetuating the cycle and denies you the chance to accept all the parts of you.
Once you can begin to accept that the bits you don't like are there for a reason and they might have even kept you safe (or saved your life even), you are opening the way for a much better relationship with yourself. With that in place, you can then pave the way for much healthier and boundaried relationships with others. Most importantly, you can start living an authentic life.