I am on the fence.
I had a boyfriend when I was 21/22, and had been with him for 2 years, and he disliked my (so-called) best friend who I had known since we were 9 or 10. He disliked her because she constantly let me down, shit on me, dumped me in favour of her current boyfriend, (each one lasted 3 or 4 months,) and she dropped me like a red hot brick in favour of her latest bloke or another mate. She also borrowed money from me and never gave it back. He was never horrible to her, he just didn't engage with her and walked off when he saw her coming (so I'd stay there a few minutes taking to her alone.)
When we were 24, I had been with him for 3 years, and she said she was getting married to the bloke she had been with for 6 months, and it was just 8 weeks away. I got no invite. I was hugely insulted and upset, and angry, as we had been friends around 15 years (two thirds of our life so far!) I found out a few weeks after that my DP being cold with her, was the reason I was not invited.
Me and my DP (now my DH,) bought a house shortly after, 17 miles away in another county, and I ceased contact with her. She left me 3 or 4 answerphone messages, asking me to call her and we can go out for a drink. I thought 'fuck off, you couldn't be arsed to invite me to your bloody wedding, just coz you dislike my partner, so fuck off.' She had invited about 10 other friends, and had 5 of them as bridesmaids. But no invite for me. 
She gave up in the end and the friendship was dead. I saw her several times over some 3 or 4 years after in passing, and I ignored her. I wonder if she ever realised why. She must be as thick as two short planks if she doesn't know.
So your friend needs to be careful. Friendships die in situations like this.