I think you should not admit to reading the messages as this will cloud the ongoing issues you have with your family members, and shift the focus of the attention (or inevitable fall-out) which will result in you laying yourself open to more criticism.
Instead, perhaps you should look on the contents of those texts as unfiltered and honest information about how your family members view you, whether you like this or not. Of course I understand how this must be devastating for you but I would urge caution in reacting angrily in defence and suggest you take some time to gather your thoughts and decide how you want to proceed.
I want to gently suggest that you need to look at your behaviour and reactions, perhaps by exploring this through counselling rather than discussing with a friend who will not want to add to your hurt by being honest enough. If all of your family feel this way and accuse you of not listening and so on, it seems obvious that many of the faults may lie with you.
It seems to me that you must change some aspects of your behaviour as you seem to ignore what your nearest and dearest have tried to point out over many years. Perhaps you need to acknowledge their difficulties in dealing with you and ask yourself if the criticisms are valid. For example, ARE you ’drama queen’? Are you judgemental with your children and others? Opinionated? What are the situations when you are accused of not listening?
It can’t be easy to feel betrayed like this, and of course I do understand your hurt feelings, but I must say that rather than a deliberate betrayal, their intention in these private messages is to share their own hurt and frustrations with each other about you.
Do you see what I am getting at? You have had a glimpse into how your family members regard you, it was not a deliberate act to hurt you any more than any other chats, phone call discussions or emails without you present. We all speak freely when criticising others who are not present and we may speak more honestly too.
I think you must lick your wounds and try to stay calm. We can all get stuck in a rut or a cycle of behaviour which isn’t good for us or others around us BUT we each have the opportunity change and grow and improve ourselves.
I wish you well and hope you can resolve some of these issues by talking to a professional so that you can approach your husband first, as your soul mate, to discuss how you should then proceed to reconnect with your family members.