Translation:I saw your husband walking with Anne.
Well, nice mot-a-mot translation, unfortunately the Romanian meaning is far away from that. Even when John walks his dog, we won't say ”Ion umblă cu câinele”, but ”Ion își plimbă câinele”, unless they walk aimlessly and they prefer each-other's company instead of other people's. But especially when we talk about two persons of opposite sexes and say "A umblă cu B” it means invariable ”A has an affair with B” (like in romance, sex, not business). The expression ”a umbla cu ceva/cineva” itself has a very negative connotation in Romanian, see for example ”a umbla cu păr în nas”, ”a umbla cu cioara vopsită” (both said about a cheater, prankster, person that is dishonest and tries to fool you), ”a umbla (cuiva) la măsele” (to beat somebody, as a punishment, but all these expressions have more complex and deep meanings), and other similar.
[edit: we also say ”el/ea/ei/ele umblă cu Dumnezeu înainte” (textually, with the God walking in front of him/her/them) about somebody that is very lucky or never fails in his/her/their tasks]