It's natural for young love to revel in their love
passion and shower each other with lovely messages and such. But as
you progress further into your relationship - to sustain a
relationship requires more than just that lovey SMS.
Don't get me wrong - it's always good to be loving and send
something thoughtful or affectionate, but that shouldn't be the
source of your problem.
Often, it's how the person developed emotionally.
Not everyone is apt to be affectionate.
You will be surprised knowing how some people demonstrate their
affection in love. It's not because they don't love their partners
- but rather, their environment and personal development had grown
in such a way that they are unable to respond to love spontaneously
and heartily.
Next time when you witness a large group of friends laugh together,
watch carefully: you will realise that although the term 'laughter'
is experienced by all - everybody will react differently to this
experience, in terms of how they display their mirth.
Some will burst out in madness; some will tear; some will only
giggle; some will remain cold; some will roll on the floor; some
will only smile; some will cover their mouth when they laugh; some
will appear like seizure; some will be clutching their chest... so
on and so forth.
It's not about 'turning to be like these' as your title has
suggested - it's probably part her to behave in such a manner in
her most natural state and form. During honeymoon stage and the
chase, most of us would attempt to conceal our flaws and negative
aspects of our personality. It's only when we have led our
relationship and given enough time, our blemish becomes
clear.
Relationship is not a journey of perfect bliss. You have probably
board the wrong train if you are expecting one.
It's how you uncover about each other's true personality, deal with
them and grow from there. That takes years of effort to compromise,
shape and evolve one another and especially to craft your
relationship. Now that you know more about her and your
relationship, start structuring basis communication - relating
individual needs and definition of love. Try to blend indifference
into something workable and learn to fine tune regularly to keep it
in shape.
If you even perturbing over such minor roadblocks, I can only say:
please anticipate more of such challenges, with greater intensity,
thrown into your path. 
Cheers
