I (M26) feel like my girlfriend (F25) is slowly losing interest after 2 years together

r/,

We been dating for 2 years and at the start she was so loving and sweet
Lately she just feels distant like she dont care anymore
When I text her she takes hours to reply but she always online for everyone else
I try to plan dates but she says she too tired or busy
It hurts because I still give effort and she just acts cold
I asked if something is wrong but she says im imagining it
I feel like she’s falling out of love and im scared to admit it
Should I wait and see or talk again and risk pushing her away

TL;DR
Girlfriend (F25) acts distant and I (M26) afraid she lost feelings after 2 years