Let G be a real Lie group,
$\Lambda <G$
a lattice and
$H\leqslant G$
a connected semisimple subgroup without compact factors and with finite center. We define the notion of H-expanding measures
$\mu $
on H and, applying recent work of Eskin–Lindenstrauss, prove that
$\mu $
-stationary probability measures on
$G/\Lambda $
are homogeneous. Transferring a construction by Benoist–Quint and drawing on ideas of Eskin–Mirzakhani–Mohammadi, we construct Lyapunov/Margulis functions to show that H-expanding random walks on
$G/\Lambda $
satisfy a recurrence condition and that homogeneous subspaces are repelling. Combined with a countability result, this allows us to prove equidistribution of trajectories in
$G/\Lambda $
for H-expanding random walks and to obtain orbit closure descriptions. Finally, elaborating on an idea of Simmons–Weiss, we deduce Birkhoff genericity of a class of measures with respect to some diagonal flows and extend their applications to Diophantine approximation on similarity fractals to a nonconformal and weighted setting.