Have you told him about how you truly feel about this marriage? Have you asked him how he feels about this marriage? If not, perhaps you could tell him what you told us here and more, then follow that up with the suggestion of couples therapy. If you think he tolerates you and simply doesn't want to go through another divorce (again, something that maybe you could tell him) then surely he might consider the idea then?

How about divorce? Neither of you seem to be happy in this relationship

If he doesn't want to try to improve the relationship.. perhaps you can force him with an ultimatum?