I Get Attached Too Easily

For as long as I can remember, I have always been the first person to fall in love. To make matters worse, I can never fall for someone practical. It is very discouraging to love someone with all your heart when you know you could never have them. It happens to me all the time. I wish there was a pill that you could take that would help you get over love sickness. It has happened again. why does this always happen?