Anyone here have a 2 year relationship curse?

So my friend says she has a two year curse (basically after spending two years with a guy things go down hill) She says she just doesn’t feel in love like when the relationship first started so she figures its time to end the relationship once she starts to feel restless. She has a baby with the guy she’s with right now so I think she should keep trying to make it work but she wants out and is starting to flirt with other guys which will eventually lead to her cheating. Anyways my question is: Are there any Girls/Guys that also feel this way and why do you feel like this? Also do keep trying to make it work or do you just leave? I’m just curious to see what others say so thanks for reading and answering.
Anyone here have a 2 year relationship curse?
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