Yes, many of us have that feeling of imminent death and a feeling of being exception too, and that feeds years and years of fear and progressive loss of life quality. This is because we suffer a complex disorder in which mood disorder is a key feature. For some of us it resolves in a terms between 1 and 2 years, for some in 3 (I mean mood disorder, not BFS, fascics probably would never stop completely and would burst again in response on every stress, same for weird neurological signs and symptomes, same for GIT symptomes etc.). So you could just wait for several years believeing that time the healer would bring its reward... It will, believe me. For sure.
But I must admit that whatever doctors later would call that disorder (and they already come to conclusion that certain physical features, like stubborn acid reflus, hypermobility of joints, allergies (especially most weird like cold allergy for example), pains without inflammation, twithcing etc. oftem are combines with the anxiety and mood disorders into a comples syndrome), thery (and we) must consider it as a lifelong condition. It never resolves fully in a mental side too and needs a great care and attention from now on.
For most of us start of the symptoms, both physical and mental, coincides well with a significant stress - chronic, accumulated or acute. Therer is something in our life, for which our mind thinks - "I would not/I should not survive this" - and we start to consider ourselves imminently dying soon (because we all kknow we will die, but not tomorrow - and this is not true for people suffering BFS at the stage of imminent death fears). IN BFS the only difference is that this feeling of soon death, due to presence of twitching and other symptomes, creates a fear od dying from ALS, unlie from other similar conditions, e.g., cancerophobia (which some of our fellows also experience).
So we could wait or could take control in the meantime, which means psychotherapy with the root questions individual of course, but generally aiming to understand which was a root event leading to premature death fear, and what does this fear mean for each of us, or how to really survive harsh times with less damage. I've seen here very different people. It was a boy with a car accident in the medical history - he survived, but paid with a several years of fears, it was a brilliant young woman surviving well over 10 highly stressful events in few years, I have seen people losing their friends or relatives to ALS, cancer, just sudden death, there was a man who nearly lost a child due to accident, several people with military, police or fire fighting background, there were people which had to move to other country, people who lost lnong term pets, people who just married or got expected and beloved children, I have seen fresh students and of course numerous doctors here - all kinds of stresses - from darkest to the brightest, from death to marriage and maternity - and it appears that reaction is the same - "I can not/I should not survive this", and the result is the same, a premature death fears. For some of fellows it ruined the lives, not as much as ALS could do, but quite significantly. That is why I believe that psychotherapy is important for us. It changes life approach. It makes us more prone to survival, let's say.
Many of us also have detectable (and often treatable) physical components, like thyroid issues (which strongly affect the mood by the way), chronic inflammation (one of our fellows had a MAGIC healing of both physical and mental symptomes after a
very strong anti-inflammatory therpay), some have inherited autoimmune disease which also need care, but on top of that taking care about the spirit is also important.
so, as a summary, answering your question 'what helps': time helps, psychotherapy helps, sometimes drugs as SSRi could help - but they help much better in conjunction with psychotherpapy of course. There are also new drugs coming on the market (in a next few years, final clinical trials are on the way) dealing specifically with endorphine reward system which is heavily involved in mental part of our condition (fear of imminent death while not being deadly ill is a HUGE source of endorphines via fear and reassurance cycle, but as any substance abuse, it is devastating, no matter that you do not need a drug dealer, you are yours' own one), so we would be able to break the vitious circle more efficiently.
hope this long and passionate speech would be of some help. I am well known adept of psychotherapy here just becasue it helps

)))