The former Poison frontman, who has been with partner Kristi Gibson for 16 years and has daughters Raine, 10, and Jorja, 5, from the relationship, told People that he is still not entirely sure that marriage is the best thing for every couple.
Michaels explained: "Love and marriage are the ultimate, but I still get a little sweaty about the marriage thing - I don't know why.
"I just hope, should Kristi and I go further, that it doesn't become this thing that in my mind crushes my free spirit."
He added: "I know this sounds crazy, and I say it's a mental issue, but I don't want to ruin it by getting engaged. And she hasn't done anything wrong, but I feel like something's not right, and it ruins our relationship."
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