She's not totally to blame but something weird went on with their 'relationship'.
He was effectively groomed by her as she was very much the teenage boys poster woman back then.
Then they start going together when he's a grown up boy and very soon after she is pregnant
She moves into his Surrey mansion with her mother and brother (!!)
Allegedly he moves out and into London. Eventually selling the house and 1-2 years ago the DM publishes the deed from Cheryl's new home, he partially bought it too.
I think she chewed him up and spit him out.
I do agree it is weird they ended up in a relationship when the first time they met she was 24 and he was 15. But also she had no contact with him beyond a three-minute audition and a bootcamp performance that year, and not much contact in 2010 either since she didn't mentor One Direction.
She might've used him for a baby and spat him out, or maybe not since I remember her saying in 2014 (even after she married the French guy) she didn't plan on having children. I think Liam has also indicated that her pregnancy in 2016/17 was unplanned. From what they've said about the split and how Liam said having Bear "ruined" his relationship with Cheryl, it seems like he was the one who ended things because he didn't like the responsibility that came with family life. We'll never know for sure, but since then Liam has been the one chewing up and spitting out several different girls.
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In fairness we don’t know if she makes it hard for him to see him.
True, although I definitely don't think she made it difficult in the early days after her split. Maybe since then with Liam seeming to return to old... habits... she's started trying to reduce his contact with Bear (although it's not like it was much in the first place anyway, considering he chose to miss the first three or four birthday parties to focus on his barely alive career).
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Edit: I feel like I'm coming across as a Cheryl defender which I'm not. I think Cheryl also has her own issues and has made some very questionable decisions. I just think that at least Cheryl seems to be a dedicated mother, whereas Liam hasn't exactly embraced fatherhood and is very immature and so deserves to be criticised for that.