i can only speak for myself...i don't fall in love or out of love too quickly at all. it takes time for me to even say i love you and when i do i mean it. however, if i see certain things in my love's behavior that seems out of line i will take pause. if this behavior continues then i will talk to him about it. if it then continues, then i will start to mentally pull back and watch him. now he will not know that i am doing this, i am looking to see if his words are matching his actions. i am at this moment still in love but if i see his behavior continue i will again to talk to him telling them exactly what i am seeing and experiencing from his actions and/or words.
if this continues, i will cut it off eventhough i am still in love...then i will go through a process of grieving for the relationship and for some unexplained reason one day something will snap and i won't have feelings for that person anymore. the crying will stop and i will be anew and i will go on. i never go back to an old love, not even to kiss them. when it is over it is over. i am not like some people who go back and fourth....and i think this shocks some people who are used to that back and fourth behavior. so to the person on the other side it does look like i fell out of love quickly but it took a lot of bullsh*t from them to get me there.
the end.