Separated and into a male friend, how can I tell if he is interested?

I'm married but have been separated from my husband - who suffers from an untreated mental illness and can't see it - for over 5 months. We are planning to get a no-fault divorce once we have lived in separate places for one year, as our state law requires. For some time, I was hanging onto hope that my husband would get better and we could work things out. But recently, I have realized I need to let go - and I am now officially separated. In the meantime, I have developed serious feelings for a good friend who is also a band-mate, in a band that I care about a lot. This friend has been very supportive during the whole mess with my husband. Ever since I've known this friend (c. 3 years), he was with his girlfriend and I was with my then-boyfriend, now-husband. But he has since broken up, and I have since gone through this ordeal with my husband. The question at hand is: how do I tell my friend that I'm interested in being more than friends with him? It's complicated not only because I have to consider my band, but also because of this unique situation with my deteriorating marriage. I know that my friend cares for me and will go out of his way to help me, but I don't know if he is attracted to me. I'm afraid of ****ing everything up by saying something - but also afraid of ****ing everything up by not saying anything. Help!