Most people would say that while it is nice to hear of ectopic survival stories, they are only able to survive because they are abdominal pregnancies, rather than tubal pregnancies which are assumed to have a 0% survival rate. I would like to present some facts to the contrary.
First of all, Not all tubal pregnancies result in a sudden massive hemorrhage. Sometimes there are smaller ruptures which can even go undiagnosed for long periods of time. The most common danger with this type of rupture are the long term effects of inflammation. Sometimes they resolve on their own. 
Secondly, some abdominal pregnancies began as tubal pregnancies. It is worth quoting this passage from the 2003 case study, “Full Term Viable Pregnancy: a case report and review” 
We would conjecture that abdominal pregnancies are either primary when an ovum from an ovary with an abnormal anatomical or functional tubo-ovarian relationship is fertilised by a spermatozoon migrating transabdominally through the Fallopian tube, with implantation on some of the abdominal viscera, or, secondary, as a result from reimplantation of a tubal abortion or expansion of an area of implantation through a ruptured tube.
As demonstrated in this case, abdominal pregnancies may culminate in the production of a full-term live baby. This may pose an ethical, moral, philosophical and religious dilemma as to managing an early and still viable abdominal pregnancy.
In other words, abdominal pregnancies sometimes start out that way with the embryo traveling the wrong way and winding up in the abdominal cavity where it implants on some organ. OR it first implants in the tube, and is later released into the abdominal cavity through a break in the tube.
Further evidence of this phenomom is a review of 44 cases of “advanced ectopic pregnancies” in a 1982 article by Dr. Clark. There were three types of ectopic pregnancies reviewed: group A, tubal abortions; group B, tubal ruptures; and group C, uterine tears. It was found that the tissue from a developing placenta was capable of relocating from the tube or uterus to various sites in the abdomen. There was a 10-30% live birth rate from these cases, 28% for those which relocated from tubal ruptures. 
 Chronic Ectopic Pregnancy, Primary Surgery: Volume One
 Full Term Viable Pregancy: a case report and review, Badria 2003
 Embryo Transfer In Vivo, Clark 1892