Hello yuihjk: To be honest, I don't know as I am the best person to be offering you advice with regard to your particular concern.

There are other members, here on PC, who may be better able to do so. However I see this is your first post here on PC. So I thought I would say... welcome to PsychCentral!

I hope you find PC to be of benefit.
I guess the one thing I can say is that you never know how disclosing your sexual orientation to a straight friend is going to be received. It may not be a big deal at all. Or it could be a friendship killer. There's simply no way to know for sure until you do it.

I would hate to think you would never have any close women friends as a result of the feelings you can sometimes develop for them. Friendships are an important part of life. Plus they contribute significantly to good health & peace of mind. But I also understand that hiding your true feelings can, as you wrote, be emotionally draining too. So it's a dilemma.
How can you tell your friend you occasionally need a break from her because you love her too much? I would have to say I personally cannot envision how that conversation would go without disclosing your true feelings for your friend. I think that, without disclosing your bisexuality, it would likely confuse your friend & perhaps cause her to begin to think perhaps you really just don't want to be friends anymore.
I don't know if you see, or have thought about seeing a counselor or therapist, or if this is something that might be a possibility for you. But if you could I think it might be helpful to have someone, in real life, with whom you could talk this situation through.

To my mind there aren't any simple answers here. There are just different ways to look at the situation & different choices you can make each with it's own potential set of benefits & pitfalls.
One additional forum, here on PC, that may be of interest to you is the relationships & communication forum. You might consider posting there as well with regard to your concern. Here's a link:
https://forums.psychcentral.com/rela...communication/
I wish you well...