How do I find something out with out any proof?

So for the past 5 months I’ve been super in love with this guy. He took my vcard and I kind of had really strong feelings for him etc. I have this friend. We hang out a lot and I thought we were friends but she is sometimes a little snide and has weird comments about me. Anywho. There hav been a couple instances where I feel like is weird. I think she is talking to him or something. It’s just a knack. I have no proof or even a little amount of speculation but the things that I keep noticing. For example one time I asked to see his snap because I blocked it. But she refused. Then another time she says if u notice he posts on snap more than any other all Why are you watch this social? I’m losing my mind rn. How do I get the answers? I don’t want to seem crazy for asking by I need to know
How do I find something out with out any proof?
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