no lexa you are not alone. there are millions of normal, mentally challenged and physically challenged people that can move on rather quickly without emotions when break ups and other things happen to them. it doesnt make you cold or heartless.

for some people its just part of their cultural background, there are cultures that teach children from a very young age to move on from the downfalls of life rather than letting emotions rule their actions, thoughts,

for some people its how they are raised. there are many people who are raised with the pick yourself up by your boot straps and move on parenting. with this kind of parenting the positives are reinforced and negatives passed off like ok so that happened , thats life get back on the horse and ride so to speak.

for some people they are taught at a very young age that emotions dont matter or its reinforced to not feel your emotions or as the saying goes they get something negative or painful reaction from their parents for expressing that emotion.

for some people medications can case a person to not feel, not be able to express their emotions appropriately and being able to move on quickly from downfalls. example I know many people on antidepressants that have this problem.

for some people its part of their mental disorder or physical problem that prevents them from feeling\expressing emotions. people with autism, ptsd, depression, and yes dissociative disorders can have what my location calls ....lack of affect (the inability to feel and express emotions )

my point is you are not alone there are millions upon millions of reasons some normal some not so normal depending upon ones location, upbringing, culture and other circumstances can cause this same problem.

my suggestion is if this continues to bother you contact a treatment provider, if there is a medical or mental reason behind why this is happening to you rather than normal for you, your treatment providers can help you sot hat it doesnt keep happening.