Inanna_Tarot: I also find 11-The Web & 13-Death very similar, & have gotten them mixed up if I do not look at the card numbers or the entire image. Even what they represent appear to be the same: death, initiation/life, rebirth; however, there is a difference in their application.
In the cosmic scheme of life, all forms of life are intrinsically linked as of the same origin, from One Source. The concept is what one part does or how it reacts affects all other parts due to that connection. The Web has that intrinsic quality of cause & effect. In the Great Web (Circle) of Life presided over by Goddess, we are each represented by a thread. Each thread is woven betwixt all others & thus part of a greater whole. That infers how we each maintain our individual thread impacts all other threads. If one thread is not stable, it compromises the stability of the others or forces others to take up the slack. As one's awareness & consciousness grows of the wholistic pattern, we can seek to become more attuned to its subtleties & contribute the individual efforts to maintaining The Web for the good of the whole.
Death is a part of the cycle of life for without death--the old dying to make way for the new--there can be no life. The two dualities are linked to each other & harken back to The Web. In Death, we have already undergone the prior cycle of 12-Sacrifice (which can also be seen as an initiatory process) wherein we give up an old life pattern to enter a new pattern. That Death is 13 is significant as it pertains to the 13 lunar months which at their end marks the end of the Wheel of the Year or a cycle. The Death experience need not necessarily mean physical death. It can refer to the major life experiences as union, separation, losses or an actual birth. As a marker of the figurative to literal ending, it can represent any life change or evolution that perforce requires its recognition & redress. How one approaches this transformative experience will determine the ease or difficulty of passage.