<human>: Could you distill the essence of the text into 1-3 sentences?

I [24F] have been in a very happy, healthy relationship for about a year. My boyfriend [25M] is my best friend and I can really see a happy future for us. We have talked about eventually getting married. However, I recently developed a friendship with another guy [27M] that made me see some holes in my current relationship. 

This other guy has expressed that he has feelings for me, and I have developed strong feelings, too. We've talked about it, and he respects that I'm in a committed relationship and can't act on my feelings. At the same time, I know that if I were single, I would undoubtedly want to pursue this new relationship. 

I never would've described my current relationship as lacking in any way. But meeting this new guy led me to realize some key gaps in my present relationship. For example, BF and I rarely have serious conversations. With this new guy, I find myself having deep, thought-provoking conversation and being intellectually satisfied. My current BF is not immature, but he certainly relies on me to help motivate him to manage his finances, career, etc. This other guy has his life together and just seems so much more mature. He and I have very similar values and outlooks on life, whereas my boyfriend and I tend to epitomize the "opposites attract" mentality. 

The two guys couldn't be more different. It's like they fulfill different parts of me, and I can't say for certain which relationship/future would be happier. They're just different kinds of happy. 

I guess I'm just looking for some advice about how to know whether I should continue investing in this current relationship, or if I need to take a chance on this new potential. If I were single, I know without a doubt that I would explore this new friendship/relationship. But I feel like it would break my BF's heart to end things when, by all appearances, things look to be happy and going well. Do I give up my current relationship, which is certain, for the chance that this could be better?
<bot>: In LTR, but met someone new. How do I know whether or not to take a chance on this new crush?