I have been married for a couple of years (been with her three) and I have found it more difficult to cum from a blow job. I used to have a hard time not cumming when she put her mouth on me. My other relationships either were not as long or in the one that was longer than 3 years - she didn't like oral so I got it seldom and wasn't allowed to cum. Is this normal? I love oral sex. She still can cum when I go down on her, but less commonly the other way around. Any suggestions???