It depends on how the relationship is going, if this relationship is a toxic situation it will definitely effect your health. Some of the symptoms are always stressed, extreme anxiety, mood changes and sleeping problems. To fix this, simply cut off the other person or if possible, try to fix things.
Antibodies, antigens are the bad things antibodies fight :)
Punch it girlllllll fire outta that stomach girl
2,3, and 5 I'm sure those or the answers