If you are reading this, you likely want to qualify for Boston, like now. Or as soon as possible anyway.
I hope you meet your goal.
But if you don’t, just know that with hard work and smart training, it is very likely you will reach your goal one day. It just might take a little longer than you think.
If you decide to keep training, you must by all means, count the cost. Consider what it means to be dedicated to marathon training for (potentially) years. Make your decision based on that – but whatever you do, don’t think that just because a BQ didn’t happen when you thought it would, that it won’t happen in the future.
The fact of the matter is that for most marathoners, improvements come fairly easily at the beginning. For example, I ran my 2nd marathon 17 minutes faster than my first. However, typically, the faster we become the smaller the improvements from race to race. On average, I was improving only by 2 to 3 minutes in the marathons leading up to my Boston Qualifying race.
Back in 2012, where the above timeline starts, I really thought that with a little luck I could run a 3:35 to Boston Qualify. In reality, it took 3+ more years and entrance into an older age bracket before I would reach my goal. Even though my goal took longer to reach than I could have imagined back in 2012, I am so glad I kept training and improving where I could.
The key is to view each race and training cycle as a learning opportunity. The more marathons you race, the better you will become at gauging what works for you both on race day and in training. Be willing to try to new things and honestly evaluate where you might be making mistakes along the way. I wish you luck as you pursue your goal!