Take a piece of paper, write down all the pros and cons, and give each option a weight, calculate the final points. Here is an example (don't take the example seriously, it might look absurd):
Problem: Go to Wal-mart or Bay to buy cloths?
Reason Weight Wal-mart Bay
---------------------------------------------------------
Fashion 10 no yes
Buy household stuff together 5 yes no
Have food 3 yes no
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Total 8 10
Decision: Bay.
Believe me, it will work if you use it to choose BF or GF.