I know I'm prone to being in the unpopular opinion camp, but I'll share my 2c anyway.

Henrietta, I don't think a relationship is a good place for you to be at this time, because from what you've written, this relationship seems to destablize you more often than not. The fact that its a LDR really doesn't help at all...

There's just not enough opportunity for you to feel reassured and to build confidence within your relationship, and I'm afraid its placing you in repetitively dangerous predicaments.

And please don't think I'm judging you, I'm not, I used to SI too, and actually learned how to stop because I am in a healthy relationship.

If a relationship is causing more turmoil in your life than actually benefitting you and bringing contentment to your life, then that's not a healthy place to be, regardless of being inlove. That's not to say the 2 people are doing anything wrong to eachother, but they might just be wrong for eachother, or the circumstances or the timing of the relationship are just presently less than ideal. Its not neccessarily someone's fault.

I honestly fear for your safety, and even though I've shared what I think, I won't presume to have the right to tell you to leave your bf.

I agree that you definitly need counselling tho, that's something worth looking into. A therapist can guide you on the path to a healthier you, and thus you can learn to be a healthier gf in turn...