My best friend is married to an old high school friend of mine. We have all had sex together, (including my boyfriend) and since then, feelings between my best friend and I have grown.

I can't stop thinking about her. She knows how I feel, and I know how she feels too. But she is married, and I am in a committed relationship. Nothing has happened between just the two of us, however I am scared to death that something will. Our emotions are strong. We have been there for each other through a lot, and we connect on an emotional level that is SERIOUSLY mind blowing. She knows what I am thinking before I say it, and is so in tune with how I feel that she knows the instant that I am unhappy.

I want to be with her all of the time. I want her to know that I love her, and its deep. But I don't want to ruin her life, and I don't want to lose my boyfriend. I am so lost as to what I am supposed to do, feel, say, or even think. I am a time bomb waiting to explode and when I do, I am so scared that she'll get hurt.
What's worse... I don't think I can let her go. She is in a bad place too, and dealing with a lot. She needs me. I need her.

Dear god... someone please help me. I am losing my mind, and I am so tired of crying my eyes out. I am in so much pain...

First, two conflicting topics here:
1. You say she knows how you feel, but later you say you want to tell her you love her.
2. You say you have all had sex together, but later say nothing has happened yet.
Can you explain more?

My apologies for being confusing. :( Thank you for wanting to help.

1. You say she knows how you feel, but later you say you want to tell her you love her.
-She knows that I have feelings for her, however I haven't told her how strong they are. I haven't actually said "i love you" to her.

2. You say you have all had sex together, but later say nothing has happened yet.
Yes, we had a foursome together. (Myself, Her, her husband, and my boyfriend.) The both of us had always thought a lot of each other. We knew the other was beautiful, but then as we grew close... we realized there was so much more. But just between she and I, nothing sexual has happened. If something did happen, it would cause a huge problem. Her husband is very jealous, and already doesn't like the fact that she is so close to me.