That's a creative expression that exists in popular way by the youth who have ability to think and write fast and also be creative. Anyway I like this kind of expression that makes a chat funny and live.

身高不是距离。。 u think that if i am so short,only 160cm..that won't make u keep far away from me...It also means if love is ture...then height is not a problem anymore.

身高 is your body height. 身高不是距离 it doesn't make any sense. However, when it is integrated with other sentences, It is OK. This is the Chinese writting style, 时间不是问题，身高不是距离，无论身在何处，两个人相爱就可以. It say something that are acceptable, including the body height. Here, the 身高不是距离 means that the body height is not the problem for friendship or love.

in this context,身高不是距离,means I don't care about your height (if I am too short while you are so tall, or conversly blahblahblah. But anyway, the whole sentence doesn't really make sense. It sounds very very very very disgusting to me.

It's only a chinese writing style,maybe several yeas ago,a girl or a boy had created this expression,but with no reason, it became famous in china.And now, we are accustomed to the use of the expression . 身高 in this sentence doesn't have any specific meanings, it only repreents something difficult between the lovers.