Shabbat Candles

Question

Are you saying that women should not have in mind the candles when they make the blessing? If so this perhaps provides a way out for me. Years ago my wife's family had a fire, and she absolutely refuses to light Shabbat candles if we are invited out to dinner (since the candles will be left on without us being in the house). Can she make the berakhah on the electric light? If so, what is the procedure, i. e., does she turn on th elight and then make the berakhah? Finally, if the blessing is on the electric light, am I correct in saying that the practice of lighting Shabbat candles is actually a custom (an important one) but no longer a matter of halakhah, since we have alternate sources of light?