When do you know it’s beyond friendship with a woman?

Hi Ladies - Need an advice , I have this very good friend, whom I met about 4 years ago, but sort of grew close over the past few months as we share a fitness activity and are partners in the activity. We have moved to updating each other about what’s gone on in the past about all our relationships and marriage that went awry, day to day updates on what’s going on in life. We talk over the fitness activity and after that hanging out about 4-5 times a week I like her very much as a friend, we seem to be aligned on values and have good emotional chemistry, she mentioned one guy is interested in her and that she checks on him once a week to 10days, he is apparently busy pursuing a project , I am wondering if I should just enjoy the friendship or think of maturing this to a relationship. I have had a relationship that broke up about 7 months ago and feel like protecting myself. How would I know if she is open to the idea of having me as a companion.