Thank you for your words Jasmer. Yes I am currently taking medication and have been for the last 5 months, which I assume is helping me with anxiety. I also have been prescribed non-addictive sleeping tablets to help with sleep. Yes I will try and book a week away soon with my partner.
Regarding Realityhere's comments, I agree about having reservations reporting this girl to my managers. However, this week the girl has made a formal concern over my work to the managers, of which I had to sit in for 2.5 hours for a meeting, when essentially it was a failing of the girl's skills to gather information from the client to allow me to complete my work. She has got in with the managers. It's a shame as I have known my boss for many years socially, however, he has also pushed out many colleagues from the job - the business in itself is becoming slowly toxic, so I am eager to leave.
Regarding something in my background that might have influenced how I required a need in this girl, would probably be that I come from a loving, close family, and am therefore open and trusting of people. In fact, my failings would be that I didn't seek to question this girl throughout the whole situation as I was trusting of her. I should have asked her specifically when she was planning to leave her boyfriend if she was so eager I would leave my gf. I would often ask her what her parents thought of this whole situation, of which she glossed over, I assumed she was just shy, when she was probably deflecting questions.
I essentially believe in the goodness in people, yet in my life have met people who were obviously 'bad' or had questionable morals, which I could detect early on, and would therefore keep my distance. But having had no prior experience to borderline personality disorder people, I simply did not question someone who appeared to be so kind. I was attracted to her as a person because she had kind eyes, was joyous and happy, and appeared to be able to keep secrets and would therefore be trustworthy. I am an open person but don't discuss private matters openly unless I trust someone, of which I did. I even mentioned to her "I 100% trust you" which I had never said to anyone before. Therefore, she probably knew that I wouldn't try and question her.
I still trust people and friends, I just have had the incredibly unfortunate experience of her turning my life upside down. The problem for me is that initially I assumed that this situation would be just an issue for her and me, as we had been keeping things private. However, it is like a bucket of water spilling out over all my life in that since she showed her dark side, it's affected my relationship with family members (who after 7 months are tired of hearing about it), as well as shame and guilt towards my partner and also friends, many of whom are still loyal and understanding, but it doesn't stop me worrying what they now think of me. Furthermore, I have always taken great pride in my job and get much self-worth from my career - this has now become incredibly difficult - I should have told myself that getting involved with people at work is risky.
Alfamagendo - my relationship with my gf is strong, however, it has put a great strain on things, simply as I am depressed and this has consumed my mind, when before I was easygoing and enjoyed socialising. I am trying to maintain this, though when I come home every night in a sad mood from work, it is probably hard for her to always lift me up as essentially I caused this.