Montag told People magazine: "This has been a heartbreaking experience to go through, and it’s not that I don’t love Spencer, we just want different things in life,”
She added: “We’ve been together almost five years — there are assets to divide, work to be discussed, and we share our puppies.”
The surgically enhanced star has also claimed that she misses her former co-stars from The Hills, especially Lauren Conrad and Audrina Partridge.
The 23-year old took to Twitter, stating: "[I'm] watching old Hills [episodes]. I miss you @AudrinaPatridge and most of all @laurenconrad."
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