Dealing with Bisexual Feelings in a Straight Relationship

I've seen a few threads about this topic, but the last one that really applied to my situation was from 2011 so I thought I'd start it back up to seek some advice/see if people have felt the same way.

I am 19 years old, and within the past year I have started to accept the fact that I am bisexual. I tended to shy away from the title of "bi" because of the strong negative stigma attached to it - that it's a phase, that you're just confused etc. But as of lately I've come to accept that this is who I am, and that I have very strong sexual feelings for both men and women.

My problem is that I am in a committed straight relationship, going on four years. I love him more than I knew possible, and I am very happy with him. He is wonderful to me, and so understanding of my feelings. I feel terrible that I have such urges to experiment with women, but I do, and I would never want to ignore my feelings only to have resentment grow between my SO and myself. However he is the only person I have ever been with, and on top of us both being very young, I've been so conflicted about what I should do. We've talked about taking a break so I could try to experiment with women, but I've always thought of breaks as the beginnings of break ups. I know that this is the time to experiment and discover who I am, but I love him more than anything.

Basically I'm torn between taking the break and accepting the possible consequences that would come with it, or just staying with him as is and hoping that knowing that I like women is enough - in the same way that I know I like men but I don't need anyone else but him. I just worry that I won't be satisfied until I know what it's like to be with a woman.

Does anyone else have any experience with this?

 

I've jokingly mentioned it, but we talked about it and it might get weird. I know it's totally hypocritical but I'd be worried about him with the other girl, and then the logistics of finding someone that would be okay with a threesome with a couple is something he's not comfortable with.

If that could be an option without emotional consequences, I'd be so down, but we're not really into sharing each other. He's worried about holding me back, but if I take a break and I can mess around I would feel like a jerk because I know that he wouldn't mess around with other girls.