Nope. But I wish she would sometime. It grosses her out. I've had a guy do it, but his finger was too rough.
Now that I am older (in my 60's) things just don't react like they used to. One time when she was going down on me I just wasn't responding, so being that we have been together for so long, she started playing with my anus while sucking/licking my penis. She noticed how I responded and so in went the finger. And WOW!!!! that did the trick. Rock hard and hips gyrating and bucking until I was completely done. You learn how to take care of each other. On the return, I was going down on her and a similar experience, so while I tongued her clit, I stuck index finger into her vagina and she responded a bit, then I remembered what she did to me that earlier time and I inserted my middle finger into her anus. That did the trick. Actually a little too well. After she started orgasming she finally yelled.. "my god stop, too much stimulation at one time". So I finished and just grinned from ear to ear. I think I like giving her pleasure more than I like receiving it.
My wife will touch my butthole when giving me a blowjob, I love it so much! But as of now no insertion yet. I'm still eagerly awaiting the day when she does put it in, I will not resist at all. I will touch her butthole too, but she only likes it some of the time. Lately when licking her pussy, I've been going closer and closer to her butthole, hoping she'll let me do more. Hopefully when she puts her finger in mine, she'll let me do the same to her. My ultimate goal is to do anal with her, but that's going to take some time and easing into it.
The next time you're going down on her just slide you tongue over her butt hole, that's how my ex-wife got interested in anal sex. Once she experienced it, she wanted it all the time as she said she had the best orgasms during anal sex and loved me rimming her butt hole.
I had a girl do this to me for the first time in my early 20s and ever since then I've wanted every girl to do it. A blowjob alone feels great, but adding a finger in your ass only makes it better.