When my hubby and I started doing anal it was uncomfortable BUT after awhile it wasnt an issue! Now you really need to get her worked up and play a bit back there if she lets you/you want to! Try with a dildo or your fingers! Start out small/one finger and get her use to it, you dont want to tear or hurt her!
When I was with my ex-husband I could never let him even close since the first time he wanted it HE never told me and just stuck it in OMFG that hurt like hell! I would never try again, now that im re-married and love and trust my new hubby with ever bone in my body it was alot easier when you trust the person! GL I hope things work out in the end (no pun intended

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Oh IMO KY sucks lol I have never liked that stuff!