Hello dear @LookingForHope
Please know that a diagnosis of BPD is not who you are. It's not your entire personality - we are all unique individuals. Please don't let a label define who you are. You are you and all the individual uniqueness that comes with it. Not one of us can be placed into a box. If a person is diagnosed with cancer - they are not cancer, they are still themselves. There is stigma with mental illness because there are misconceptions of what it is. Which is a disease like any other that can be treated. And does not have to be for life. This is one of the main reasons I do not like labelling. Stigma is ignorance as people are afraid or judgemental of what they deem as different because they do not understand.
Mental health professionals use these labels of grouping certain symptoms together in order to help aid them to apply the best treatments for their patients. That is the idea of such diagnostic labels - nothing more and nothing less. And It's is not always foolproof or continual. Symptoms can change like with any disease and the diagnosis can change. Symptoms with proper treatment can also go away. Don't think you will have to deal with your issues for life as that is not necessarily so. Take this weight off your mind.
Living with lonliness, lack of support and isolation would rattle most people's minds and test their sanity. You are no different. Lonliness and isolation causes depression and anxiety - it's a normal response to it. Tackling these situations and exploring strategies and activities that ease and lessen the lonliness and isolation is the first port of call. If you feel you have some human flaws that are contributing to this state of isolation/lonliness then working with a psychologist to help overcome your mood swings, over-sensitivity, thought processors etc and really work on it will offer you relief. If there are health problems such as hormonal imbalances (which can also cause mood swings etc) then treating this will also help.
If you find inner anger, rage (perhaps over being hurt, abused, neglected and badly treated in the past) is ruining your relationships it's vital to talk about your repressed pain/feelings with someone and work through them. Also to work on coping strategies to control he anger when it takes hold. When with friends/loved ones "never react when angry". Walk away and then come back and deal with the situation when calm. This will save and nurture your relationships. If really distressed/angry call a therapist, a support person from a group or come on here and vent talking things through.
Its a good sign you have that fighting spirit - hold onto this as it is guiding you in the right direction. It will take time - we are all a work in progress as life is a journey and we are always evolving if we learn by our mistakes. And if we do our best and make wise choices we will find where we want to go that's a better place faster leaving the past behind us. Also leaving behind those who do not respect or value us is necessary for healing and growth.
You have as much to offer to others, the world and yourself as anybody else does and you know this deep down. Hold onto that and never let that reality go when others ignorantly put you down. You need to heal from the past and hold onto a more positive vision of the future with meaning and purpose. When you find the latter you will find you. Hold onto hope and never give up. Hugs