If your Girl friend get angry because of ....

It depends on the friends. If the friends invovle other girls then yea I would understand why she would get angry and it would be very deserving. However, if it was just me and a few buddies going out for a drink I would be confused to why she would be angry unless we had plans i forgot about or something like that.

im not a drinker , so there is no chances to happen such kind of things with me .

It is not possible, as i have never used it.

Don't let her know that.when she notice that i will tell her it is the part of the wrok.And let her know i do not want to drink,but it is the mission of the boss.The important thing is admiting your mistake.I always do like this.

i will explain to her,if she believes in me,i think she will understand me .certainly,i will buy a gift to her.