Actually, she is incorrect. Your vindication is at hand, for I, a stranger on the internet, will help you! :D
In all seriousness, she is very incorrect. The word "seems" is used to define an object based on, either because of or in spite of, previously existing information.
It seems like bananas are tastier than I previously assumed.
Especially because it seems like the gymnastics will be on later!
"Because" is used to define an objects current state of being in relation to the state of being of another object or due to a preexisting condition. Be and cause are combined, the operative portion being "cause", they come together to mean that something else is the cause.
This banana tastes bad because I don't like bananas.
Especially because the gymnastics is on later!
"Seems" is also used to express suspicion.
Your friend is wrong, so it seems.
"Seeing as" would be a much more appropriate term, as it is, indeed, synonymous with "because". Also, you could use "considering", "when", or, perhaps, "because".
I hope this wasn't too long, and I sincerely hope this helps.