Wow Jolly! This is tough. I don't really have any answers for you. I am leaning towards saying, "Be true to yourself." If you are a lesbian, than you are. It just is, whether you act on it or not.
I guess you need to ask yourself, "Is this a sexual attraction?" Can you imagine yourself engaged in sexual acts with the women you have admired and loved over the years?
Love isn't necessarily sexual. You may have been deeply in love with some of the women in your life without being a lesbian. I think that if you felt both love and sexual attraction, then you could define yourself as bisexual or lesbian. But if just love, than not.
Certainly, having an affair with a woman or a man would be hurtful to your husband. If you love him, you will want to consider that before having an affair. Yet, if you are truly a lesbian and you want to live that lifestyle and be true to yourself, than your husband deserves to be told honestly.
I am sure it wouldn't be easy on him, but living a life that deceives and cheats both of you isn't easy either.
I also think it is natural to admire or be attracted to people who are different from ourselves. You are shy while your friend is daring and takes chances. Maybe this freindship is good for you both. You can temper her daring nature while she can introduce you to new experiences.
On the other hand, be cautious. Is her daring nature a healthy one or is she manic, living on the edge, endangering herself and all those around her? If so, ask yourself why that attracts you?
I guess you need to do some soul searching. In the meantime, I don't see why you can't be friends. I am sure there will be other folks here who will disagree and I am looking forward to reading their advice.
I am 44. Over the years there have been many women I have admired and loved. I have a dear friend now, who is like your friend. She took me quarry diving this past summer and wants to climb the Presidentials in New Hampshire together next fall. She introduces me to adventure. There is absolutely nothing of a sexual attraction between us and we are both married with children. (Our chldren introduced us.)
Over the years, I have been acquainted with several lesbians. I have been fascinated by, intrigued with and draw to these women. Yet, the bottom line is, I cannot imagine ever engaging in sexual acts with them.
Can you picture yourself sexually with a woman? (No need to answer here, only to yourself.) If so, I think you have an answer.