Invitation Wording

Have an invitation-wording dilemma. My father passed away and my mother has re-married and I have not had contact with her for several years. My groom and I are paying for most of the wedding and his parents are contributing about 3-5%. I would like to acknowledge/honor the groom’s parents on the invitation. They welcomed me into the family right off the bat and treat me like I’m one of their own (and not to forget that they are kicking in some $ for the wedding, which I do very much appreciate as I know it’s not their responsibility). How can I word this with out giving the impression the groom’s parents are hosting? Maybe I don’t really need to worry about whom it looks like is doing the hosting and just list them as requesting the honour of people’s presence. Any advice is greatly appreciated.