Bonnie Wilson is James Wilson's second wife. She, along with Sam Carr, is one of James' three spouses who appeared on screen (his third wife Julie Wilson was an unseen character). She is portrayed by actress Jane Adams.
They met after House met Wilson (which was some time in the early-to-mid '90s), agreeing they only wanted to spend time with each other platonically as Bonnie was coming off a bad relationship. Their first not-date took place in Boston. However, they became intimate soon after Bonnie fell in love with him. Bonnie tells House that Wilson was genuine about being kind to her as a friend when she was heartbroken, and it was such a turn-on that she "jumped HIM"; this wasn't Wilson putting on a facade to seduce her:
Bonnie: It’s like walking into a sticky trap. Once you’re the focus of all that attention, it’s addictive... It’s the emotional stuff that really sucks you in. He’s just so knight-in-shining armor, you know? Always there to support you, until he’s not, but by then you’re hooked!
Bonnie tells House that "sex with James is fantastic" because "no one tries harder to please a woman than James Wilson". Despite this, she admits that, because of his actions and personality, if she hadn't fallen for James romantically before they connected physically it would've been easier not to get attached and not get her heart broken again.
House threw a bachelor party for Wilson that Wilson compares to the 1979 semi-pornographic movie "Caligula". James and Bonnie adopted their dog Hector while on their honeymoon. Bonnie disliked House this early in the marriage and named the untrainable dog after a (bad) anagram insulting House.
James and Bonnie split up sometime prior to the start of the series, likely by 2001 when Wilson had a brief relationship with Beth (falconer). It's possible this was the marriage when Wilson had an affair, as Bonnie says Wilson "hurt" her but at least he felt guilty about it. In Spin Wilson tells Cameron that his (unnamed) wife was wasn't sick, the marriage was fine, but he met someone who made him "feel funny...good" and he "didn't want to let that feeling go". Considering Wilson's marriage to Bonnie coincided with House's infarction, recovery, and breakup with Stacy, Bonnie's resentment over Wilson's increased caregiving role in House's life likely triggered their estrangement. However, Bonnie, like Sam, never explicitly mentions James cheating on her; her biggest complaint was feeling abandoned, emotionally and physically, when Wilson spent more time with other people who needed him (in her case, House) and became more closed-off from her.
In spite of how badly their marriage ended, by 2007 Bonnie is friendly with James and speaks of him with wistful affection. As House puts it, "[Wilson] doesn’t stop giving good advice just because you’re divorced. He’s compulsive about remaining on good terms with his exes." James paid alimony to Bonnie until Season 2, at which point Bonnie obtained her real estate license and attempted to strike out on her own. However, James called her "the worst broker in New Jersey" behind her back.
House is in touch with Bonnie occasionally, and they maintain a cordial if strained relationship. Bonnie does partially blame House for her divorce, stating that James was always there for House but not always there for her. House usually contacts Bonnie when he is trying to dig up something on Wilson. For example, he called her when he figured out Wilson was dating someone to see if it was her (it was, in fact, Amber).
She was also mentioned in the sixth season episode Wilson where Wilson bought a loft through Bonnie with House before Cuddy did to punish Cuddy for dating Lucas .